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Synthesis and Reactions of 3,3-Difluoro-2-exo-methylidene Indolines.

ABSTRACT: A dearomative electrophilic fluorination of 2-methylindoles is reported, delivering 3,3-difluoroindolines bearing an exomethylidene. The model substrate was synthesized on up to a 20 mmol scale and was purified by a practical recrystallization as a crystalline bench-stable, yet reactive solid. The olefin is amphoteric and can react both as a nucleophile and as an electrophile. A wide range of metal-free, palladium, rhodium, and copper reactions was explored, forming new C-H, C-B, C-C (alkyl and aryl), C-N, C-O, C-P, and C-S bonds.

SUBMITTER: Zeidan N

PROVIDER: S-EPMC7201399 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Synthesis and Reactions of 3,3-Difluoro-2-<i>exo</i>-methylidene Indolines.

Zeidan Nicolas N Zambri Matthew M Unger Sven S Dank Christian C Torelli Alexa A Mirabi Bijan B Lautens Mark M

Organic letters 20200410 9

A dearomative electrophilic fluorination of 2-methylindoles is reported, delivering 3,3-difluoroindolines bearing an exomethylidene. The model substrate was synthesized on up to a 20 mmol scale and was purified by a practical recrystallization as a crystalline bench-stable, yet reactive solid. The olefin is amphoteric and can react both as a nucleophile and as an electrophile. A wide range of metal-free, palladium, rhodium, and copper reactions was explored, forming new C-H, C-B, C-C (alkyl and ...[more]

PMID: 32276536

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