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Which of the following statements regarding pi MO theory is incorrect?
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pi MOs are constructed via a linear combination of a p atomic orbital on each of the atoms involved in the pi system
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If you have 4 input p atomic orbitals you should get 4 pi MOs
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MOs that have correct nodal and symmetry properties are called "canonical"
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A proper pi MO must be "symmetric" and not "antisymmetric"
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The positve combination of 2 pi MOs
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Definition
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Which of the following statements about the Diels-Alder reaction is incorrect?
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The reaction is favorable mainly due to entropy
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The retro-Diels-Alder reaction becomes favorable when benzene is one of the products
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The reaction rate is usually comtrolled by the difference in energy between the HOMO(diene) and the LUMO(dienophile)
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When regioisomers are possible, the 1,3-type adduct is the minor product
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The reaction with an alkyne as the dienophile produces a cyclohexa-1,4-diene
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Definition
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Term
Which of the following statements is generally true for SN1 reactions?
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Nearly complete inversion of configuration generally occurs
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These are favored by nonpolar solvents
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Reaction rates depend only on the concentration of the organic substrate
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These reactiosn are greatly accelerated by dipolar aprotic solvents
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The mechanism is a one-step backside attack
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Definition
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Term
What is the major product which results when (2R, 3R)-2-chloro-3-methylpentane is treated with NaOMe/MeOH?
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Z-3-methyl-2-pentene
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S-3-methyl-1-pentene
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E-3-methyl-2-pentene
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R-3-methyl-1-pentene
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Definition
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Term
Which of the following statements regarding elimination and/or substitution reactions is false?
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Weakly basic leaving groups are good leaving groups
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Dipolar aprotic solvents are superior for SN2 reactions because they don't solvate anions in solution (they allow anions to be "naked")
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Soft (polarizable) bases are better for effecting eliminations while hard bases are better for substitutions
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E2 reactions of acrylic substrates proceed predominantly in a trans-coplanar fashion
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E1 and SN1 reactions of the same substrate proceed at the same rate
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Definition
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