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Conversion of Medium-Sized Lactams to ?-Vinyl or ?-Acetylenyl Azacycles via N,O-Acetal TMS Ethers.

ABSTRACT: ?-Vinyl or ?-acetylenyl azacycles were easily synthesized from 7- to 9-membered lactams and 6- to 9-membered lactams via N,O-acetal trimethylsilyl (TMS) ethers. Organocopper and organostannane reagents afforded reasonable yields for the respective N-acyliminium ion vinylation and acetylenylation intermediates generated from N,O-acetal TMS ethers in the presence of a Lewis acid.

SUBMITTER: Kim M

PROVIDER: S-EPMC6278647 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Conversion of Medium-Sized Lactams to α-Vinyl or α-Acetylenyl Azacycles via N,O-Acetal TMS Ethers.

Kim Minjun M Jang Jaebong J Choi Goyoung G Chung Sungkyun S Lim Changjin C Hur Joonseong J Kim Hyun Su HS Na Younghwa Y Son Woo Sung WS Suh Young-Ger YG Jung Jong-Wha JW Kim Seok-Ho SH

Molecules (Basel, Switzerland) 20181119 11

α-Vinyl or α-acetylenyl azacycles were easily synthesized from 7- to 9-membered lactams and 6- to 9-membered lactams via N,O-acetal trimethylsilyl (TMS) ethers. Organocopper and organostannane reagents afforded reasonable yields for the respective N-acyliminium ion vinylation and acetylenylation intermediates generated from N,O-acetal TMS ethers in the presence of a Lewis acid. ...[more]

PMID: 30463260

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