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Bronsted Acid/Lewis Acid Cooperatively Catalyzed Addition of Diazoester to 2H-chromene Acetals.

ABSTRACT: A novel Brønsted acid/Lewis acid dual catalyst system has been developed to promote an efficient C-C bond formation between a range of oxocarbenium precursors derived from chromene acetals and ethyl diazoacetate. The reaction proceeds under mild conditions and is tolerant of common functionalized 2H-chromene and isochromene acetals. In addition, an asymmetric variant of diazoacetate addition towards 2H-chromene acetal is described. Continued investigations include the further optimization of asymmetric induction towards the formation of diazo ester substituted 2H-chromene.

SUBMITTER: Luan Y

PROVIDER: S-EPMC4233145 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Brønsted Acid/Lewis Acid Cooperatively Catalyzed Addition of Diazoester to 2H-chromene Acetals.

Luan Yi Y Qi Yue Y Gao Hongyi H Ma Qianqian Q Schaus Scott E SE

European journal of organic chemistry 20141101 31

A novel Brønsted acid/Lewis acid dual catalyst system has been developed to promote an efficient C-C bond formation between a range of oxocarbenium precursors derived from chromene acetals and ethyl diazoacetate. The reaction proceeds under mild conditions and is tolerant of common functionalized 2H-chromene and isochromene acetals. In addition, an asymmetric variant of diazoacetate addition towards 2H-chromene acetal is described. Continued investigations include the further optim ...[more]

PMID: 25411552

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