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Synthesis of pyrrolo[1,2-a]quinolines by formal 1,3-dipolar cycloaddition reactions of quinolinium salts.

ABSTRACT: Quinolinium salts, Q⁺-CH₂-CO₂Me Br^- and Q⁺-CH₂-CONMe₂ Br^- (where Q = quinoline), were prepared from quinolines. Deprotonation of these salts with triethylamine promoted the reaction of the resulting quinolinium ylides (formally azomethine ylides) with electron-poor alkenes by conjugate addition followed by cyclization or by [3 + 2] dipolar cycloaddition. The pyrroloquinoline products were formed as single regio- and stereoisomers. These could be converted to other derivatives by Suzuki-Miyaura coupling, reduction or oxidation reactions.

SUBMITTER: Choi A

PROVIDER: S-EPMC6633155 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Synthesis of pyrrolo[1,2-a]quinolines by formal 1,3-dipolar cycloaddition reactions of quinolinium salts.

Choi Anthony A Morley Rebecca M RM Coldham Iain I

Beilstein journal of organic chemistry 20190703

Quinolinium salts, Q+-CH2-CO2Me Br- and Q+-CH2-CONMe2 Br- (where Q = quinoline), were prepared from quinolines. Deprotonation of these salts with triethylamine promoted the reaction of the resulting quinolinium ylides (formally azomethine ylides) with electron-poor alkenes by conjugate addition followed by cyclization or by [3 + 2] dipolar cycloaddition. The pyrroloquinoline products were formed as single reg ...[more]

PMID: 31354865

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