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Asymmetric synthesis of primary amines via the spiroborate-catalyzed borane reduction of oxime ethers.

ABSTRACT: [reaction: see text] The enantioselective borane reduction of O-benzyloxime ethers to primary amines was studied under catalytic conditions using the spiroborate esters 5-10 derived from nonracemic 1,2-amino alcohols and ethylene glycol. Effective catalytic conditions were achieved using only 10% of catalyst 5 derived from diphenylvalinol in dioxane at 0 degrees C resulting in complete conversion to the corresponding primary amine in up to 99% ee.

SUBMITTER: Huang X

PROVIDER: S-EPMC2571073 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of primary amines via the spiroborate-catalyzed borane reduction of oxime ethers.

Huang Xiaogen X Ortiz-Marciales Margarita M Huang Kun K Stepanenko Viatcheslav V Merced Francisco G FG Ayala Angel M AM Correa Wildeliz W Jesús Melvin De MD

Organic letters 20070331 9

[reaction: see text] The enantioselective borane reduction of O-benzyloxime ethers to primary amines was studied under catalytic conditions using the spiroborate esters 5-10 derived from nonracemic 1,2-amino alcohols and ethylene glycol. Effective catalytic conditions were achieved using only 10% of catalyst 5 derived from diphenylvalinol in dioxane at 0 degrees C resulting in complete conversion to the corresponding primary amine in up to 99% ee. ...[more]

PMID: 17397177

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