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Ketenimines from Isocyanides and Allyl Carbonates: Palladium‐Catalyzed Synthesis of β,γ‐Unsaturated Amides and Tetrazoles
Author(s) -
Qiu Guanyinsheng,
Mamboury Mathias,
Wang Qian,
Zhu Jieping
Publication year - 2016
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201609034
Subject(s) - chemistry , isocyanide , hydrazoic acid , cycloaddition , catalysis , trimethylsilyl azide , silica gel , trimethylsilyl , palladium , azide , medicinal chemistry , hydrolysis , ketenimine , organic chemistry
The reaction of allyl ethyl carbonates with isocyanides in the presence of a catalytic amount of Pd(OAc) 2 provided ketenimines through β‐hydride elimination of the allyl imidoylpalladium intermediates. The insertion of the isocyanide into the π‐allyl Pd complex proceeded via an unusual η 1 ‐allyl Pd species. The resulting ketenimines were hydrolyzed to β,γ‐unsaturated carboxamides during purification by flash column chromatography on silica gel or converted in situ into 1,5‐disubstituted tetrazoles by [3+2] cycloaddition with hydrazoic acid or trimethylsilyl azide.