Vincent Davenel, C. Nisole, F. Fontaine-Vive
Sep 2, 2020
Citations
0
Influential Citations
6
Citations
Journal
The Journal of organic chemistry
Abstract
An efficient, and mild synthetic route for the preparation of functionalized bicyclo[3.2.1]oct-2-ene and bicy-clo[3.3.1]nonadiene via gold-mediated cycloisomerization of 1,6-enynes has been developed. This atom-economical catalytic process was optimized and relied on the efficiency of IPrAuNTf2 allowing the formation of functionalized bicyclic adducts in 55% to 91% isolated yields (18 products). The reliable access to bicyclic derivatives was demonstrated on a 3 g scale with a low catalyst loading. The process occurred on a 5-exo versus 6-endo pathway depending on the substitution of the alkynyl moiety. DFT calculations were performed on stability of intermediates and this study corroborated the endo:exo ratio and the mechanistic pathway with key intermediates. Reduction of the ester moiety and hydrogenation of the exo-methylene double bond of the bicyclo[3.2.1]oct-2-ene adduct illustrated the potential post-functionalization of bicyclic derivatives.