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Bis(imido)vanadium(V)-Catalyzed [2+2+1] Coupling of Alkynes and Azobenzenes Giving Multisubstituted Pyrroles.

ABSTRACT: The combination of VCl3(THF)3 and N, N-bis(trimethylsilyl)aniline (1a) is an efficient catalyst for the [2+2+1] coupling reaction of alkynes and azobenzenes, giving multisubstituted pyrroles. A plausible reaction mechanism involves the generation of a mono(imido)vanadium(III) species as an initiation step, where 1a served as an imido source with concomitant release of 2 equiv of ClSiMe3, followed by a reaction with azobenzene to form a catalytically active bis(imido)vanadium(V) species via N?N bond cleavage.

SUBMITTER: Kawakita K

PROVIDER: S-EPMC6460926 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Bis(imido)vanadium(V)-Catalyzed [2+2+1] Coupling of Alkynes and Azobenzenes Giving Multisubstituted Pyrroles.

Kawakita Kento K Beaumier Evan P EP Kakiuchi Yuya Y Tsurugi Hayato H Tonks Ian A IA Mashima Kazushi K

Journal of the American Chemical Society 20190211 10

The combination of VCl3(THF)3 and N, N-bis(trimethylsilyl)aniline (1a) is an efficient catalyst for the [2+2+1] coupling reaction of alkynes and azobenzenes, giving multisubstituted pyrroles. A plausible reaction mechanism involves the generation of a mono(imido)vanadium(III) species as an initiation step, where 1a served as an imido source with concomitant release of 2 equiv of ClSiMe3, followed by a reaction with azobenzene to form a catalytically active bis(im ...[more]

PMID: 30731038

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