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Tandem Double [3 + 2] Cycloaddition Reactions at Both C-1 and C-3 Atoms of N-Cyanomethylisoquinolinium Ylide.

ABSTRACT: The base-promoted cycloaddition reaction of N-cyanomethylisoquinolinium chloride with 2-arylidene-1,3-indanediones in dry tetrahydrofuran resulted in the expected spiro[indene-2,1'-pyrrolo[2,1-a]isoquinoline] derivatives. However, the triethylamine-promoted three-component reaction of N-cyanomethylisoquinolinium chloride, aromatic aldehydes, and two molecules of 1,3-indanediones in acetonitrile afforded unique spiro[benzo[f]imidazo[5,1,2-cd]indolizine-4,2'-indene] derivatives in satisfactory yields through tandem double [3 + 2] cycloaddition reactions.

SUBMITTER: Shi RG

PROVIDER: S-EPMC6645381 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Tandem Double [3 + 2] Cycloaddition Reactions at Both C-1 and C-3 Atoms of N-Cyanomethylisoquinolinium Ylide.

Shi Rong-Guo RG Sun Jing J Yan Chao-Guo CG

ACS omega 20171113 11

The base-promoted cycloaddition reaction of N-cyanomethylisoquinolinium chloride with 2-arylidene-1,3-indanediones in dry tetrahydrofuran resulted in the expected spiro[indene-2,1'-pyrrolo[2,1-a]isoquinoline] derivatives. However, the triethylamine-promoted three-component reaction of N-cyanomethylisoquinolinium chloride, aromatic aldehydes, and two molecules of 1,3-indanediones in acetonitrile afforded unique spiro[benzo[f]imidazo[5,1,2-cd]indolizine-4,2'-inde ...[more]

PMID: 31457339

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