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Multicomponent Mannich reactions with boron enolates derived from diazo esters and 9-BBN.

ABSTRACT: Diazo esters, arylboranes, and carbamoyl imines undergo a 3-component Mannich condensation reaction. Catalyzed by Cu(II) salts, the reaction affords the corresponding isocyanate Mannich product: one that can be easily trapped in situ by other nucleophiles. The Mannich condensation corresponds to an ?,?-disubstituted enolate addition to imines. The reaction was rendered asymmetric by using the (-)-phenylmenthol ester in good yield and selectivities.

SUBMITTER: Luan Y

PROVIDER: S-EPMC4671502 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Multicomponent Mannich reactions with boron enolates derived from diazo esters and 9-BBN.

Luan Yi Y Schaus Scott E SE

Organic letters 20110407 9

Diazo esters, arylboranes, and carbamoyl imines undergo a 3-component Mannich condensation reaction. Catalyzed by Cu(II) salts, the reaction affords the corresponding isocyanate Mannich product: one that can be easily trapped in situ by other nucleophiles. The Mannich condensation corresponds to an α,α-disubstituted enolate addition to imines. The reaction was rendered asymmetric by using the (-)-phenylmenthol ester in good yield and selectivities. ...[more]

PMID: 21473584

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