SmI2-promoted intra- and intermolecular C–C bond formation with chiral N-acyl oxazolidinones
作者:Rolf H. Taaning、Laura Thim、Jacob Karaffa、Araceli G. Campaña、Anna-Mette Hansen、Troels Skrydstrup
DOI:10.1016/j.tet.2008.09.044
日期:2008.12
The suitability of chiral oxazolidinones in the SmI2-mediated C–C bond generation between the imide functionality of an N-acyloxazolidinone unit and an olefinic radical acceptor, in both inter- and intramolecular reactions, was investigated. It was shown that the products from an Evans asymmetric alkylation can undergo direct carbon–carbon bond formation with an acrylamide providing chiral acyclic
Herein, we report an efficient iridium-catalyzed double asymmetrichydrogenation of 2,5-dialkylienecyclopentanones, delivering the chiral 2,5-disubstituted cyclopentanones in excellent yields and stereoselectivities. The results of the kinetic experiments and control experiments indicated that the two C═C bonds were hydrogenated in a stepwise manner and the second stereocenter was synergistically controlled