Generation of Endocyclic Vinyl Carbene Complexes via Gold-Catalyzed Oxidative Cyclization of Terminal Diynes: Toward Naphthoquinones and Carbazolequinones

Autor: Tian-You Li, Qing Sun, Rai-Shung Liu, Bo Zhou, Chao Shu, Xin Lu, Qiao He, Long-Wu Ye, Chong-Yang Shi
Rok vydání: 2018
Předmět:
Zdroj: ACS Catalysis. 9:1019-1025
ISSN: 2155-5435
DOI: 10.1021/acscatal.8b04455
Popis: Carbene cascade reactions involving carbene/alkyne metathesis have attracted much attention over the past decades because this chemistry offers great potential to build complicated cyclic molecules. However, the formed vinyl metal carbenoids in these reactions are limited to exocyclic carbenes, and the generation of endocyclic vinyl carbene complexes remains unexplored. Here, we report an unprecedented gold-catalyzed oxidative cyclization of terminal diynes. Importantly, the generation of endocyclic vinyl carbene complexes was involved in this oxidative cyclization, which is distinctively different from previous protocols. This method allows the facile synthesis of various valuable naphthoquinones and carbazolequinones from readily available diynes under exceptionally mild reaction conditions and features a broad substrate scope and wide functional group tolerance. Moreover, theoretical calculations provide further evidence on the divergent selectivity of this cyclization reaction.
Databáze: OpenAIRE