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Enantioselective aldehyde alpha-nitroalkylation via oxidative organocatalysis.

ABSTRACT: The first enantioselective organocatalytic alpha-nitroalkylation of aldehydes has been accomplished. The aforementioned process involves the oxidative coupling of an enamine intermediate, generated transiently via condensation of an amine catalyst with an aldehyde, with a silyl nitronate to produce a beta-nitroaldehyde. Two methods, one that furnishes the syn beta-nitroaldehyde and a second that provides access to the anti isomer, have been developed. Data are presented to support a hypothesis that explains this phenomenon in terms of a silyl group-controlled change in mechanism. Finally, a three-step procedure for the synthesis of both syn- and anti-alpha,beta-disubstituted beta-amino acids is presented.

SUBMITTER: Wilson JE

PROVIDER: S-EPMC3259685 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Enantioselective aldehyde alpha-nitroalkylation via oxidative organocatalysis.

Wilson Jonathan E JE Casarez Anthony D AD MacMillan David W C DW

Journal of the American Chemical Society 20090801 32

The first enantioselective organocatalytic alpha-nitroalkylation of aldehydes has been accomplished. The aforementioned process involves the oxidative coupling of an enamine intermediate, generated transiently via condensation of an amine catalyst with an aldehyde, with a silyl nitronate to produce a beta-nitroaldehyde. Two methods, one that furnishes the syn beta-nitroaldehyde and a second that provides access to the anti isomer, have been developed. Data are presented to support a hypothesis t ...[more]

PMID: 19627154

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