Term
| A __________ (or __________) is a reaction in which a hydroxyl group is added to each end of a double bonded alkene. |
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Definition
1) Hydroxylation
2) Dihydroxylation |
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Term
| __________ of an alkene followed by acidic hydrolysis gives __________ hydroxylation of the double bond. |
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Definition
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Term
__________ __________ (OsO4, sometimes called __________ __________) reacts with alkenes in a concerted step form a cyclic osmate ester.
Oxidizing agents such as __________ __________ (H2O2) or tertiary __________ oxides (R3N+-O-) are used to hydrolyze the osmate ester and reoxidize osmium to __________ __________.
The regenerated __________ __________ catalyst continues to hydroxylate more molecules of the alkene. |
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Definition
1) Osmium tetroxide
2) Osmic acid
3) Hydrogen peroxide
4) Amine
5) Osmium tetroxide
6) Osmium tetroxide |
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Term
| In the hydroxylation of osmium tetroxide, since the two carbon-oxygen bonds are formed simultaneously with the cyclic __________ __________, the __________ atoms add to the same face if the double bond; that is, with __________ stereochemistry. |
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Definition
1) Osmate ester
2) Oxygen
3) Syn |
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Term
A cold, dilute solution of __________ __________ also hydroxylates alkenes with __________ stereochemistry, with slightly reduced yields.
Like osmium tetroxide, __________ __________ adds to the alkene double bond to form a cyclic ester: a __________ ester in this case.
The __________ solution hydrolyzes the manganate ester, liberating the __________ and produce a brown precipitate of manganese dioxide. |
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Definition
1) Potassium permanganate
2) Syn
3) Potassium permanganate
4) Manganate
5) Basic
6) Glycol |
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Term
To hydroxylate an alkene with __________ stereochemistry, which is the better reagent: __________ __________ or __________ __________? It depends on the circumstances:
If the starting material is only 2 mg of a compound 15 steps along in a difficult synthesis, we use __________ __________.
If the hydroxylation is the first step in a synthesis and involves 5 kg of the starting material, we use __________ __________. |
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Definition
1) Syn
2) Osmium tetroxide
3) Potassium permanganate
4) Osmium tetroxide
5) Potassium permanganate |
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