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The vinylogous aldol reaction of unsaturated esters and enolizable aldehydes using the novel Lewis acid aluminum tris(2,6-di-2-naphthylphenoxide).

ABSTRACT: The synthesis of the novel Lewis acid, aluminum tris(2,6-di-2-naphthylphenoxide) (ATNP), and its use in the vinylogous aldol reaction between methyl crotonate and enolizable aldehydes are described. ATNP is related to Yamamoto's Lewis acid, aluminum tris(2,6-diphenylphenoxide) (ATPH), but the 2-naphthyl groups more effectively block the ?-position of aldehydes, enabling the selective enolization of crotonate esters in the presence of enolizable aldehydes. Vinylogous aldol reactions then proceed smoothly and in high yields with a variety of substrates.

SUBMITTER: Gazaille JA

PROVIDER: S-EPMC3427784 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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The vinylogous aldol reaction of unsaturated esters and enolizable aldehydes using the novel Lewis acid aluminum tris(2,6-di-2-naphthylphenoxide).

Gazaille Jeffrey A JA Sammakia Tarek T

Organic letters 20120523 11

The synthesis of the novel Lewis acid, aluminum tris(2,6-di-2-naphthylphenoxide) (ATNP), and its use in the vinylogous aldol reaction between methyl crotonate and enolizable aldehydes are described. ATNP is related to Yamamoto's Lewis acid, aluminum tris(2,6-diphenylphenoxide) (ATPH), but the 2-naphthyl groups more effectively block the α-position of aldehydes, enabling the selective enolization of crotonate esters in the presence of enolizable aldehydes. Vinylogous aldol reactions then proceed ...[more]

PMID: 22621176

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