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Generation of stereochemically defined tetrasubstituted enolborinates by 1,4-hydroboration of ?,?-unsaturated morpholine carboxamides with (diisopinocampheyl)borane.

ABSTRACT: On all fours: The title reaction with (Ipc)2 BH provides tetrasubstituted enolborinates which undergo aldol reactions with aldehydes to form products with all-carbon quaternary centers with exceptional diastereo- and enantioselectivity. A change to the substitution pattern of the starting amide leads to either diastereomer of the ?-methyl-?-ethyl-?-hydroxy carboxamide (1 or 2).

SUBMITTER: Allais C

PROVIDER: S-EPMC3910328 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Generation of stereochemically defined tetrasubstituted enolborinates by 1,4-hydroboration of α,β-unsaturated morpholine carboxamides with (diisopinocampheyl)borane.

Allais Christophe C Tsai Andy S AS Nuhant Philippe P Roush William R WR

Angewandte Chemie (International ed. in English) 20131015 49

On all fours: The title reaction with (Ipc)2 BH provides tetrasubstituted enolborinates which undergo aldol reactions with aldehydes to form products with all-carbon quaternary centers with exceptional diastereo- and enantioselectivity. A change to the substitution pattern of the starting amide leads to either diastereomer of the α-methyl-α-ethyl-β-hydroxy carboxamide (1 or 2). ...[more]

PMID: 24281884

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