Term
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Definition
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Term
the reason for handedness in molecules: |
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Definition
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Term
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Definition
molecules that contain no plane of symmetry and are not superimposeable on their mirror-images |
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Term
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Definition
a C bonded to 4 different groups |
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Term
some groups that can't be chirality centers |
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Definition
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Term
optically active substances |
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Definition
substances that, when in solution, rotate the plane of plane-polarized light |
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Term
the angle of rotation of optically active substances can be measured with... |
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Definition
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Term
some things about a substance's rotation that can be measured |
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Definition
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Term
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Definition
a compound whose solution rotates plane-polarized light to the right |
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Term
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Definition
a compound whose solution rotates plane-polarized light to the left |
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Term
the extent of rotation depends on... |
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Definition
-concentration -path length -wave length |
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Term
|
Definition
the optical rotation of a chiral compound under standard conditions, such as concentration of 1g/mL, sample path length of 1 dm, and light of wavelength 589 nm |
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Term
rules for assigning configurations at a chirality center |
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Definition
1: assign priorites to each group bonded to the C by using Cahn-Ingold-Prelog rules 2: orient the molecule so that the group of lowest priority is pointing to the rear 3: draw a curved arrow from group 1 to group 2 to group 3 4: if the arrow rotates clockwise, the chirality center is R, and if the arrow rotates counterclockwise, the chirality center is S |
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Term
how to assign priorites to each group bonded to the C by using Cahn-Ingold-Prelog rules |
|
Definition
1: rank each atom by atomic number (atoms with higher atomic numbers get higher priorities) 2: if a decision can't be reached based on the first atom, look at a second or third atom until a difference is found 3: multiple bonded atoms are equivalent to the same number as single bonded atoms |
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Term
is the sign of optical rotation related to R, S designation? |
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Definition
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Term
how R, S designations have been proven to be correct |
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Definition
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Term
a molecule with 2 chirality centers can have how many possible stereoisomers? |
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Definition
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Term
depiction of the relationship between enantiomers and diastereoisomers |
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Definition
photograph figure 5-10 on p. 131 |
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Term
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Definition
stereoisomers that are not mirror images |
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Term
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Definition
diastereoisomers whose configuration differs at only 1 chirality center |
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Term
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Definition
occurs when a compound with 2 chirality centers possesses a plane of symmetry |
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Term
a meso compound is ______ despite having 2 chirality centers |
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Definition
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Term
a meso compound is achiral despite ______ |
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Definition
having 2 chirality centers |
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Term
racemic mixture (racemate) |
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Definition
a 50:50 mixture of 2 enantiomers |
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Term
the optical rotation of racemic mixtures |
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Definition
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Term
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Definition
differ in connections between atoms |
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Term
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Definition
have different C skeletons |
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Term
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Definition
contain different functional groups |
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Term
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Definition
have functional groups in different positions |
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Term
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Definition
have the same connections between atoms, but different geometry |
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Term
types of diastereoisomers |
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Definition
-configurational diastereoisomers -cis-trans isomers |
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Term
how cis-trans isomers differ |
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Definition
they differ in the arrangement of substituents on a ring or a double bond |
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Term
other elements that can be chirality centers |
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Definition
other elements wit tetrahedral atoms |
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Term
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Definition
able to be converted from achiral to chiral in a single chemical step |
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Term
how to identify prochirality for a sp2 hybridized C |
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Definition
1: draw the plane that includes the atoms bonded to that sp2 C
2: assign priorities to the groups bonded to that C
3: draw a curved arrow from group 1 to group 2 to group 3
4: the face of the plane on which the curved arrow rotates clockwise is the Re face
5: the face on which the arrow rotates counterclockwise is the Si face |
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Term
when an atom that is sp3 hybridized has a prochirality center |
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Definition
when it becomes a chirality center after one of its attached groups is replaced |
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Term
how to identify prochirality in an sp3 hybridized atom |
|
Definition
1: for CH2X, imagine a replacement of 1 H with deuterium
2: rank the groups, including deuterium
3: if the replacement leads to R chirality, the atom is pro-R
4: if the replacement leads to S chirality, the atom is pro-S |
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Term
when a C is not a stereocenter |
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Definition
when it has 2 of the same group attached to it |
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Term
how to determine whether the stereocenter has the R or S configuration |
|
Definition
1: give each of the 4 groups a number (1-4) 2: use the orientation of these numbers to determine the configuration |
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Term
how to assign numbers to the groups around a stereocenter |
|
Definition
1: make a list of the 4 atoms attached to the stereocenter 2: rank those atoms based on atomic number |
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Term
|
Definition
compound that has an internal plane of symmetry |
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Term
when compounds are chiral |
|
Definition
when they have stereocenters and they and are not meso |
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Term
|
Definition
compound makes plane polarized light rotate clockwise |
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Term
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Definition
compound makes plane polarized light rotate counterclockwise |
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Term
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Definition
rotates polarized light clockwise
given a minus (+) sign |
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Term
|
Definition
rotates polarized light counterclockwise
given a minus (-) sign |
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Term
the number of stereoisomers a molecule with chirality centers can have |
|
Definition
2n stereoisomers, where n = # of chirality centers |
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Term
|
Definition
atom whose replacement leads to an R chirality |
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Term
|
Definition
atom whose replacement leads to an S chirality |
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Term
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Definition
the face on which the arrows curve clockwise |
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Term
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Definition
the face on which the arrows curve counterclockwise |
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Term
types of organic reactions |
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Definition
-addition -elimination -substitution -rearrangement |
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Term
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Definition
occur when 2 reactants add to form one product, with no atoms left over
A + B --> AB |
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Term
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Definition
occur when a single reactant splits into 2 products
AB --> A + B |
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Term
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Definition
occur when 2 reactants exchange parts to yield 2 new products
AB + CD --> AD + CB |
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Term
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Definition
occur when a single product undergoes a rearrangement of bonds to yield an isomeric product
ABCD --> DBCA |
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Term
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Definition
describes the bonds broken and formed in a chemical reaction, and accounts for all reactants and products |
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Term
types of bond breaking in chemical reactions |
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Definition
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Term
|
Definition
symmetrical bond breakinbg such that 1 electron remains with each fragment |
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Term
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Definition
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Term
heterolytic bond breaking |
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Definition
unsymmetrical bond breaking such that both electrons remain with one fragment and the other fragment has a vacant orbital |
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Term
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Definition
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Term
types of bond formation in chemical reactions |
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Definition
-symmetrical -unsymmetrical |
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Term
symmetrical bond formation |
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Definition
each reactant contributes 1 electron to a covalent bond |
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Term
depiction of symmetrical bond formation |
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Definition
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Term
unsymmetrical bond formation |
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Definition
both electrons in a covalent bond come from 1 reactant |
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Term
depiction of unsymmetrical bond formation |
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Definition
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Term
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Definition
-radical -polar -pericyclic |
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Term
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Definition
involve symmetrical bond breaking and bond formation |
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Term
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Definition
involve unsymmetrical bond breaking and bond formation |
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Term
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Definition
reactant that contains an atom with an unpaired electron |
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Term
why radicals are highly reactive |
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Definition
because they contain an atom with an unpaired electron |
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Term
substitution reaction that involves a radical |
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Definition
occurs when a radical abstracts an atom and a bonding electron from another molecule |
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Term
addition reaction that involves a radical |
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Definition
occurs when a radical adds to a double bond |
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Term
steps in a radical reaction |
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Definition
-initiation step -propagation steps -termination step |
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Term
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Definition
produces radicals by the symmetrical clevage of a bond |
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Term
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Definition
chain reaction where a radical abstracts an atom to produce a new radical and a stable molecule |
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Term
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Definition
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Term
how bond breaking and formation works in radical reactions |
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Definition
all bonds are formed and broken by reactions of species with odd numbers of electrons |
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Term
some characteristics of polar reactions |
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Definition
-they occur as a result of differences in bond polarities within molecules -electron-rich sites in 1 molecule react with electron-poor sites in another molecule -the movement of electron pairs is shown by curved, fullheaded arrows -the reacting species are nucleophiles and electrophiles -many polar reactions can be explained in terms of acid-base reactions |
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Term
polar reactions occur as a result of... |
|
Definition
differences in bond polarities within molecules |
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Term
the polarities within polar molecules are usually due to... |
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Definition
electronegativity differences between atoms |
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Term
electronegativity differences may also be due to... |
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Definition
-interactions of functional groups with solvents -interactions of functional groups with Lewis acids or bases |
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Term
if there's no real electronegativity difference between atoms in a molecule, how can that bond behave as a polar bond? |
|
Definition
some bonds in which 1 atom is polarizeable may also behave as polar bonds |
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Term
the sites that react in polar reactions |
|
Definition
the electron-rich sites in one molecule react with the electron-poor sites in another molecule |
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Term
the movement of an electron pair in a polar reaction is shown by... |
|
Definition
a curved, fullheaded arrow |
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Term
the reacting spevcies in a polar reaction |
|
Definition
-nucleophile -electrophile -some compounds behave as both nucleophiles and electrophiles |
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Term
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Definition
compound with electron-rich atom |
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Term
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Definition
compound with electron-poor atom |
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Term
many polar reactions can be explained in terms of... |
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Definition
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Term
an example of a polar reaction |
|
Definition
addition of HBr to ethylene |
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Term
what type of addition is the addition of HBr to ethylene? |
|
Definition
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|
Term
the behavior of the π electrons in ethylene in the addition of HBr to ethylene |
|
Definition
the π electrons in ethylene behave as a nucleophile |
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Term
how the reaction of the addition of HBr to ethylene begins |
|
Definition
the attack of the π electrons on the electrophile H+ |
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Term
what happens at the end of the reaction of the addition of HBr to ethylene? |
|
Definition
the resulting intermediate carbocation reacts with Br- to form bromoethana |
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Term
rules for using curved arrows in polar reaction mechanisms |
|
Definition
-electrons must move from nucleophile to electrophile -nucleophile can be negative or neutral -electrophile can be positive or neutral -the octet rule must be followed |
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Term
how chemical reactions can be expressed as equilibria |
|
Definition
all chemical reactions are equilibria that can be expressed by an equilibrium constant (Keq) that shows the ratio of products to reactants |
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Term
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Definition
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Term
|
Definition
|
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Term
what must the energy be for the reaction to proceed as written? |
|
Definition
to proceed as written, the energy of the products must be lower than the energy of the reactants |
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Term
the energy change that occurs during a reaction is described by... |
|
Definition
ΔG°, the Gibbs free-energy change |
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Term
favorable reaction (spontaneous) |
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Definition
have negative ΔG° and are exothermic |
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Term
unfavorable reaction (nonspontaneous) |
|
Definition
have positive ΔG° and are endothermic |
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Term
the relationship between ΔG° and Keq |
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Definition
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Term
|
Definition
enthalpy, which is a measure of the total change in bonding energy during a reaction |
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Term
|
Definition
the reaction is exothermic |
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Term
|
Definition
the reaction is endothermic |
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Term
|
Definition
entropy, which is a measure of the freedom of motion of a reaction |
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|
Term
rxn with positive entropy |
|
Definition
produces 2 product molecules from 1 reactant molecule |
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Term
rxn with negative entropy |
|
Definition
produces 1 product molecule from 2 reactant molecules |
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|
Term
relationship between ΔG°, ΔH°, and ΔS° |
|
Definition
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|
Term
bond dissociation energy (D) |
|
Definition
measures the heat needed to break a bond to produce 2 radical fragments |
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|
Term
what happens to the strength of bonds in exothermic reactions? |
|
Definition
the bonds formed are stronger than the bonds broken |
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|
Term
what reaction energy diagrams show |
|
Definition
the energy changes that occur during a reaction |
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|
Term
how a reaction energy diagram is set up |
|
Definition
vertical axis represents energy changes and horizontal axis represents the progress of the reaction |
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|
Term
the highest energy species in a reaction |
|
Definition
|
|
Term
can a reaction have more than 1 transition state? |
|
Definition
|
|
Term
the energy of activation (ΔG‡) |
|
Definition
the difference in energy between the reactants and the transition state |
|
|
Term
values of ΔG‡ range from... |
|
Definition
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|
Term
what a reaction can do after reaching the transition state |
|
Definition
it can go on to form products or revert to starting material |
|
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Term
|
Definition
in a reaction of at least 2 steps, this is the species that lies at the energy minimum between 2 transition states |
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|
Term
energy of an intermediate |
|
Definition
even though it lies between 2 transition states, it is a highg energy species |
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|
Term
can an intertmediate be isolated? |
|
Definition
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|
Term
the solvents laboratory reactions are carried out in |
|
Definition
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|
Term
the medium biological reactions occur in |
|
Definition
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|
Term
the temperatures laboratory reactions take place in |
|
Definition
a wide range of temperatures |
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|
Term
the temperatures biological reactions take place in |
|
Definition
the temperature of the organism, usually within narrow limits |
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|
Term
the catalyzing in laboratory reactions |
|
Definition
uncatalyzed or use simple catalysts |
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|
Term
the catalyzing in biological reactions |
|
Definition
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|
Term
description of laboratory reagents |
|
Definition
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|
Term
description of biological reagents |
|
Definition
involve large, complex coenzymes |
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Term
specificity of biological reactions |
|
Definition
they have high specificity for substrate |
|
|
Term
specificity of laboratory reactions |
|
Definition
they are relatively nonspecific |
|
|
Term
are atoms w/ vacant orbitals electrophiles or nucleophiles? |
|
Definition
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|
Term
a type of rxn that has a carbocation intermediate |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
activation energy vs. speed of rxn |
|
Definition
the higher the activation energy, the slower the rxn |
|
|
Term
are pi bonds electrophiles or nucleophiles? |
|
Definition
|
|
Term
are aromatic rings electrophiles or nucleophiles? |
|
Definition
|
|
Term
the difference between exothermic and exergonic |
|
Definition
exothermic = -ΔH° exergonic = -ΔG° |
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|
Term
the difference between endothermic and endergonic |
|
Definition
endothermic = +ΔH° endergonic = +ΔG° |
|
|
Term
location of transition state in energy diagram |
|
Definition
|
|
Term
location of intermediate in energy diagram |
|
Definition
|
|
Term
|
Definition
hydrocarbon that contains a C=C bond |
|
|
Term
the 2 most important organic chemicals produced industrially |
|
Definition
|
|
Term
how ethylene, propylene, and butylene are synthesized |
|
Definition
|
|
Term
|
Definition
involves homolytic breaking of C-H and C-C bonds |
|
|
Term
thermal cracking reactions are dominated by... |
|
Definition
|
|
Term
|
Definition
describes the number of multiple bonds and/or rings in a molecule |
|
|
Term
how to calculate the degree of unsaturation of a compound |
|
Definition
1: determine the equivalent hydrocarbon formula of the compound 2: add the number of halogens to the number of H's 3: subtract 1 H for every N 4: ignore the number of O's 5: calculate the number of paire of H's that would be present in an alkane that has the same number of C's as the equivalent hydrocarbon of the compound of interest. te difference is the degree of unsaturation. |
|
|
Term
|
Definition
1: find the longest chain containing the 2bl bond, and name it using "ene" as the suffix
2: number the C atoms in the chain, beginning at the end nearer the double bond
3: number the substituents and write the name
4: for cycloalkenes, the double bond is between C1 and C2, and substituents receive the lowest possible numbers
5: a -CH2- substituent is a methylene group, a H2C=CH- group is a vinyl group, and a H2C=CHCH2- group is an allyl group |
|
|
Term
the hybridization of VC atoms in a double bond |
|
Definition
|
|
Term
the bonds formed in the 2bl bond between 2 C's |
|
Definition
1 sigma bond and 1 pi bond |
|
|
Term
does free rotation occur around 2bl bonds? |
|
Definition
|
|
Term
|
Definition
disubstituted alkene that has substituents on the same side of the double bond |
|
|
Term
trans isomer of an alkene |
|
Definition
disubstituted alkene that has substituents on different sides of the double bond |
|
|
Term
do cis and trans isomers of alkenes interconvert? |
|
Definition
no because of the rigidity of the 2bl bond |
|
|
Term
when cis-trans isomerism in an alkene doesn't occur |
|
Definition
when one C in the 2bl bond is bonded to identical substituents |
|
|
Term
what the E, Z system of isomerism is used for |
|
Definition
it's used to describe the arrangement of substituents around a 2bl bond that can't be described by the cis/trans system |
|
|
Term
|
Definition
1: for each 2bl bonded C, rank its substituents by atomic number (kinda like you assign priorities in R and S configurations) 2: if a decision can't be reached based on the 1st atom, look at the 2nd or 3rd atom until a difference is found 3: multiple bonded atoms are equivalent to the same number of single bonded atoms |
|
|
Term
|
Definition
has the higher ranked groups on the same side of the 2bl bond |
|
|
Term
|
Definition
has the higher ranked groups on opposite sides of the double bond |
|
|
Term
which alkenes are more stable, cis or trans? |
|
Definition
|
|
Term
why are trans alkenes more stable than cis alkenes? |
|
Definition
because cis alkenes have steric strain between the double bond substituents |
|
|
Term
stabilities of alkenes can be determined experimentally by measuring... |
|
Definition
-cis-trans e'librium constants -heats of hydrogenation |
|
|
Term
the most useful method for determining the stability of alkenes |
|
Definition
by measuring the heats of hydrogenation |
|
|
Term
heat of hydrogenation of a cis isomer vs that for a trans isomer |
|
Definition
the heat of hydrogenation of a cis isomer is a larger negative number thatn the heat of hydrogenation of a trans isomer |
|
|
Term
which alkene is of higher energy, cis or trans isomer? |
|
Definition
|
|
Term
alkene 2bl bonds become more stable with... |
|
Definition
|
|
Term
why alkene 2bl bonds become more stable with increasing substitution |
|
Definition
-hyperconjugation
-more substituted double bonds have more of the stronger sp2-sp3 bonds |
|
|
Term
|
Definition
stabilizing interaction between the antibonding pi orbital of the C-C bond and a filled C-H sigma orbital oh an adjacent substituent |
|
|
Term
electrophilic addition reactions |
|
Definition
addition of an electrophile to a C=C bond to yield a saturated product |
|
|
Term
mechanism of the electrophilic addition of H-X to alkenes |
|
Definition
1: the electrons of the nucleophilic pi bond attack the H atom of the electrophile H-X (X = Cl, Br, I, OH)
2: 2 electrons from the pi bond form a new sigma bond between -H and an alkene C
3: the carbocation intermediate reacts with X- to form a C-X bond |
|
|
Term
description of the energy diagram for the electrophilic addition of H-X to alkenes |
|
Definition
-has 2 peaks separated by a valley (carbocation intermediate) -the reaxtion is exothermic -the first step is slower than the second step |
|
|
Term
Markovinikov's rule of orientation of addition reactions |
|
Definition
-in the addition of HX to a double bond, H attaches to the C with fewer substituents and X attaches to the C with more substituents (regiospecific) -if the C's have the same number of substituents, a mixture of products results |
|
|
Term
|
Definition
describes a reaction that occurs with a specific regiochemistry to give a single product rather than a mixture of products |
|
|
Term
the structure of carbocations |
|
Definition
planar; the unoccupied p orbital extends above and below the plane containing the cation |
|
|
Term
the stability of carbocations increases with... |
|
Definition
|
|
Term
carbocation stability can be measured by... |
|
Definition
studying gas phase dissociation enthalpies |
|
|
Term
carbocations can be stabilized by... |
|
Definition
-inductive effects ofg neighhboring alkyl groups -hyperconjugation |
|
|
Term
how a carbocation can be stabilized by hyperconjugation |
|
Definition
the mnore alkyl groups on the carbocation, the more opportunities there are for hyperconjugation |
|
|
Term
|
Definition
postulate stating that we can get a picture of what a given transition state looks like by looking at the structure of the nearest stable species |
|
|
Term
exothermic reactions have transition states that resemble... |
|
Definition
|
|
Term
endothermic reactions have transition states that resemble... |
|
Definition
|
|
Term
why the transition state for an endothermic step resembles the product of that step |
|
Definition
because it is closer in energy |
|
|
Term
why the transition state for an exothermic step resembles the reactant of that step |
|
Definition
because it is closer in energy |
|
|
Term
in an electrophilic addition reaction, the transition state for alkene protonation resembles... |
|
Definition
the carbocation intermediate |
|
|
Term
more stable carbocations form faster because... |
|
Definition
their transition states are also stabilized |
|
|
Term
reactions in which products from carbocation rearrangements are formed |
|
Definition
some electrophilic addition reactions |
|
|
Term
the formation of products from carbocation rearrangements supports... |
|
Definition
the 2 step electrophilic addition mechanism, in which an intermediate carbocation is formed |
|
|
Term
how intermediate carbocations can rearrange to more stable carbocations |
|
Definition
-a hydride shift -an alkyl shift |
|
|
Term
|
Definition
the shift of a H atom and its electron pair to a nearby cationic center |
|
|
Term
|
Definition
the shift of an alkyl group with its electron pair to a nearby cationic center |
|
|
Term
why a compound with an OH group has a higher boiling point than an otherwise identical compound with a lone O |
|
Definition
|
|
Term
stability vs. ΔHcombustion |
|
Definition
|
|
Term
energy of bond vs. size of atoms involved |
|
Definition
|
|
Term
what kind of addition is it when alkene double bonds add to a carbocation? |
|
Definition
|
|
Term
how rings contribute to unsaturation |
|
Definition
each ring is an extra degree of unsaturation |
|
|
Term
when numbering the carbons in a chain, what gets priority? functional group or branching? |
|
Definition
|
|
Term
when to put a number next to the E or Z |
|
Definition
when there's more than 1 alkene in a chain |
|
|
Term
nucleophilic substitution |
|
Definition
swapping of 1 functional group for another |
|
|
Term
rate of nucleophilic substitution reaction depends on... |
|
Definition
concentration of both nucleophile and alkyl halide |
|
|
Term
solvents in which reaction occurs faster |
|
Definition
|
|
Term
rate law for nucleophilic reactions |
|
Definition
rate = k [substrate][nucleophile] |
|
|
Term
why polar solvents are better thannonpolar solvents for reactions to occur in |
|
Definition
because of the charges involved |
|
|
Term
|
Definition
-polar protic -polar aprotic |
|
|
Term
|
Definition
|
|
Term
|
Definition
bas a dipole moment but can't H bond |
|
|
Term
why the reactivity of halides in polar aprotic solvents reverses (F- > Cl- > Br- > I-) |
|
Definition
because there is no H bonding to solvent |
|
|
Term
what makes a good leaving group? |
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Definition
leaving groups are weal bases |
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Term
steric bulk on a particular atom vs. that atom's nucleophilicity |
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Definition
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Term
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Definition
the loss of a leaving group from the alpha C and a H from the beta C resulting in the formation of a double bond |
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Term
why the major product of an elimination reaction is the more substituted alkene |
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Definition
because alkenes become more thermodynamically stable as C-H bonds are replaced with C-C bonds |
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Term
periodic trand in bacisity |
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Definition
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Term
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Definition
2 groups on adjacent C's oriented at 180° to each other
[image] |
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Term
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Definition
2 groups on adjacent C's oriented 0° to each other
[image] |
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Term
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Definition
2 groups on adjacent C's oriented 60° to each other
[image] |
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Term
eclipsed (stereochemistry) |
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Definition
when all 3 substituents overlap completely with all 3 substituents on a neighboring C
[image] |
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Term
staggered (stereochemistry) |
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Definition
when all 3 substituents on a C are arranged at a 60° angle to all 3 substituents on another C
[image] |
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Term
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Definition
50:50 mixture of 2 enantiomers |
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Term
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Definition
molecule with chiral centers, but has a plane of symmetry that makes the molecule achiral |
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Term
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Definition
strain that arises from the proximity of bonds (and the electrons in them) - generally eclipsing |
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Term
difference between conformational isomers |
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Definition
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Term
physical properties of conformational isomers |
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Definition
identical, as long as they can interconvert thru bond rotation |
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Term
difference between constitutional isomers |
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Definition
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Term
physical properties of constitutional isomers |
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Definition
different boiling points, melting points, and other physical properties |
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Term
difference between stereoisomers |
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Definition
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Term
physical properties of enantiomers |
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Definition
identical, but differ in optical rotation |
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Term
physical properties of diastereomers |
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Definition
different boiling points, melting points, etc. |
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Term
another name for stereoisomers |
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Definition
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Term
what happens to the axial and equatorial groups when the chair flips? |
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Definition
the axial groups become equatorial and the equatorial groups become axial |
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Term
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Definition
atoms or molecules that contain an unpaired electron in their valence shell |
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Term
why free radicals are highly reactive |
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Definition
because they contain less than a full octet of electrons |
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Term
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Definition
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Term
what stabilizes free radicals? |
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Definition
the same factors that stabilize carbocations
-substitution -resonance -with adjacent lone pairs -polarizability -hybridization -electron-withdrawing groups |
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Term
electron-poor species, like radicals, are stabilized by... |
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Definition
electron rich neighbors or being able to spread electron density over a greater volume |
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Term
substituted radicals in order of stability |
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Definition
tertiary > secondary > primary > methyl radical |
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Term
how resonance can stabilize radicals |
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Definition
radicals are stabilized if they can be delocalized over several atoms (as in resonance) |
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Term
how adjacent lone pairs stabilize free radicals |
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Definition
hyperconjugation
stability increases with increasing donor ability of atom with lone pairs |
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Term
how polarizability stabilizes free radicals |
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Definition
stability increases with increasing size of the atom |
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Term
how hybridization affects free radical stability |
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Definition
stability increases with decreasing s-character, which moves the free radical further from the nucleus |
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Term
stability of free radical vs. s-character |
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Definition
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Term
electron-withdrawing groups |
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Definition
groups that withdraw electron density from the free radical (without being able to donate a lone pair); they destabilize radicals |
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Term
bond strength vs. kcal/mol |
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Definition
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Term
how electron movement is shown in homolytic cleavage |
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Definition
using "single-barbed" arrows |
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Term
the arrows used to show electron movement in resonance of free radicale |
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Definition
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Term
the 3 key mechanistic steps in free radical halogenation |
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Definition
-initiation -propagation -termination |
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Term
initiation phase of free radical halogenation |
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Definition
homolytic cleavage of bond between halogen atoms |
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Term
propagation phase of free radical halogenation |
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Definition
step in the free radical reaction that starts with free radicals from the initiation phase yields free radicals |
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Term
termination phase of free radical halogenation |
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Definition
free radicals bonding to each other such that there are no free radicals left |
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Term
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Definition
they generate free radicals when heated
they usually have a weak bond (such as O-O) that readily undergoes homolytic cleavage |
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Term
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Definition
C wit 3 H attached; basically primary C |
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Term
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Definition
C with 2 H attached; basically secondary C |
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Term
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Definition
C with 1 H attached; basically tertiary C |
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Term
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Definition
C with 0 H attached; basically quartenary C |
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Term
how many lines to draw on the 13C spectrum |
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Definition
the number of unique C's plus symmetrical pairs |
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Term
when to make a line on the 13C spectrum short |
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Definition
when there's no H attached to it |
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Term
the lines to put to the left of 100 ppm on the 13C spectrum |
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Definition
the ones associated with the sp2 hybridized C's |
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Term
the lines to put to the right of 100 ppm on the 13C spectrum |
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Definition
the ones associated with the sp3 hybridized C's |
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Term
rate law in electrophilic reactions |
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Definition
rate = k [alkene][electrophile] |
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Term
Hammond's postulate basically says... |
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Definition
the transition state most closely resembles product or reactant, whichever is closest in energy to the transition state |
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Term
anything can move during a rearrangement, as long as... |
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Definition
it's moving towards more stable carbocation |
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Term
going from less stable to more stable is (endothermic or exothermic)? |
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Definition
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Term
why one possible reactant might be a better option than other possible reactants for the same product |
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Definition
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Term
where to put the sp3 C's attached to halogens on the 13C spectrum |
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Definition
between the 100 and the C's to the far right |
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Term
where to put the sp2 C's attached to O on the 13C spectrum |
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Definition
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Term
where to put the sp2 C's on the 13C spectrum |
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Definition
a little to the left of 100ppm |
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Term
the range of the 13C spectrum |
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Definition
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Term
orientation of the 13C spectrum |
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Definition
200 on left, 0 on right, and 100 in middle |
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Term
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Definition
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Term
generic rate law for electrophilic addition |
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Definition
rate = k [alkene][electrophile] |
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Term
how C's in a chain can be electrophilic centers |
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Definition
if there's a partial positive charge on them due to dipole moment caused by polarity of what they're bonded with |
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Term
how bonds are broken in polar reactions |
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Definition
heterolytically (electron pair moves instead of single electron) |
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Term
where to put the sp C's in the 13C NMR spectrum |
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Definition
in the middle, straddling the 100ppm in the middle |
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Term
where to put the sp3 C's in the 13C NMR spectrum |
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Definition
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Term
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Definition
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Term
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Definition
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Term
the alkene expected to react faster in an electrophilic addition reaction based on Hammond's postulate |
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Definition
the one that yields a more stable carbocation |
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Term
can ring C double bonds isomerize? |
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Definition
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