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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Generation and trapping of cyclopentenylidene gold species: four pathways to polycyclic compounds
Gilles Lemière1, Vincent Gandon, Kevin Cariou
1UPMC Paris 06, Laboratoire de Chimie Organique (UMR CNRS 7611), Institut de Chimie Moléculaire (FR 2769), case 229, 4 place Jussieu, F-75252 Paris cedex 05, France.
Abstract:
Cyclopentenylidene gold complexes can easily be formed from vinyl allenes through a Nazarov-like mechanism. Such carbenes may transform in four different ways into polycyclic frameworks: electrophilic cyclopropanation, C-H insertion, C-C migration, or proton shift. We have studied the selectivity of these different pathways and used our findings for the expedient preparation of valuable complex molecules. An application to the total synthesis of a natural product, Delta(9(12))-capnellene, is presented. DFT computations were carried out to shed light on the mechanisms.
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