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1,3-Dipolar cycloaddition of isatin N,N'-cyclic azomethine imines with α,β-unsaturated aldehydes catalyzed by DBU in water.

ABSTRACT: A simple and green procedure was established by [3 + 3] cycloaddition reaction of isatin derived cyclic imine 1,3-dipoles with α,β-unsaturated aldehydes, giving the desired spiro heterocyclic oxindoles with aza-quaternary centers in good yields and diastereoselectivities. It should be noted that water can be employed as a suitable solvent for the improvement of diastereoselectivity.

SUBMITTER: Wang ZY

PROVIDER: S-EPMC9055116 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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1,3-Dipolar cycloaddition of isatin N,N'-cyclic azomethine imines with α,β-unsaturated aldehydes catalyzed by DBU in water.

Wang Zhan-Yong ZY Yang Ting T Chen Rongxiang R Ma Xueji X Liu Huan H Wang Kai-Kai KK

RSC advances 20200625 41

A simple and green procedure was established by [3 + 3] cycloaddition reaction of isatin derived cyclic imine 1,3-dipoles with α,β-unsaturated aldehydes, giving the desired spiro heterocyclic oxindoles with aza-quaternary centers in good yields and diastereoselectivities. It should be noted that water can be employed as a suitable solvent for the improvement of diastereoselectivity. ...[more]

PMID: 35516173

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