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Asymmetric Petasis Borono-Mannich Allylation Reactions Catalyzed by Chiral Biphenols.

ABSTRACT: Chiral biphenols catalyze the asymmetric Petasis borono-Mannich allylation of aldehydes and amines through the use of a bench-stable allyldioxaborolane. The reaction proceeds via a two-step, one-pot process and requires 2-8 mole?% of 3,3'-Ph2 -BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99?%) and high enantioselectivies (er up to 99:1). The catalytic reaction is a true multicomponent condensation reaction whereas both the aldehyde and the amine can possess a wide range of structural and electronic properties. Use of crotyldioxaborolane in the reaction results in stereodivergent products with anti- and syn-diastereomers both in good diastereoselectivities and enantioselectivities from the corresponding E- and Z-borolane stereoisomers.

SUBMITTER: Jiang Y

PROVIDER: S-EPMC5716625 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Asymmetric Petasis Borono-Mannich Allylation Reactions Catalyzed by Chiral Biphenols.

Jiang Yao Y Schaus Scott E SE

Angewandte Chemie (International ed. in English) 20170104 6

Chiral biphenols catalyze the asymmetric Petasis borono-Mannich allylation of aldehydes and amines through the use of a bench-stable allyldioxaborolane. The reaction proceeds via a two-step, one-pot process and requires 2-8 mole % of 3,3'-Ph<sub>2</sub> -BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99 %) and high enantioselectivies (er up to 99:1). The catalytic reaction is a true multicomponent condensation reac ...[more]

PMID: 28052567

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