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Intramolecular Umpolung Synthesis of Exocyclic ?-Amino Alcohols through Decarboxylative Amination.

ABSTRACT: An intramolecular aminative Umpolung cyclization strategy has been developed by using ?,?-diphenylglycine (2) as the amination and Umpolung reagent. Aldehydes (1) bearing an additional carbonyl group underwent condensation with ?,?-diphenylglycine to form an imine, decarboxylation to generate a delocalized 2-azaallylanion, and subsequent intramolecular Umpolung cyclization to produce a variety of exocyclic ?-amino alcohols (6) in 60-93% yields with up to >20:1 trans/cis selectivity under mild conditions.

SUBMITTER: Chen J

PROVIDER: S-EPMC6644024 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Intramolecular Umpolung Synthesis of Exocyclic β-Amino Alcohols through Decarboxylative Amination.

Chen Jianfeng J Tian Jiaxin J Liu Feng F Liu Yong Y Zhao Guoqing G Yuan Weicheng W Zhao Baoguo B

ACS omega 20181101 11

An intramolecular aminative Umpolung cyclization strategy has been developed by using α,α-diphenylglycine (2) as the amination and Umpolung reagent. Aldehydes (1) bearing an additional carbonyl group underwent condensation with α,α-diphenylglycine to form an imine, decarboxylation to generate a delocalized 2-azaallylanion, and subsequent intramolecular Umpolung cyclization to produce a variety of exocyclic β-amino alcohols (6) in 60-93% yields with up to >20:1 trans/cis sele ...[more]

PMID: 31458145

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