Publication Details (including relevant citation information):
J. Am. Chem. Soc. 2012, 134, 7570-7574
A. P. Pulis and V. K. Aggarwal
Enantioenriched secondary allylic carbamates have been deprotonated with sBuLi and reacted with boronic esters. In contrast to other electrophiles, high α-selectivity was observed and the boronate complexes were formed with almost complete retention of stereochemistry. The boronate complexes underwent a stereospecific 1,2-migration leading to tertiary allylic boronic esters with high er (>98:2). The scope of the reaction has been explored and found to embrace a broad range of both allylic carbamates and boronic esters. The methodology has been applied to an eight-step, stereoselective synthesis of each of the diastereoisomers of C30 botryococcene.
Address (URL): http://pubs.acs.org/doi/abs/10.1021/ja303022d