Enantioselective α-benzoyloxylation of ketones promoted by primary amine catalyst

摘要

A mixture of 9-amino-(9-deoxy)epi-dihydroquinidine and salicylic acid was able to promote the direct reaction of various cyclohexanones with dibenzoyl peroxide, thus affording the corresponding protected α-hydroxy carbonyl compounds in high yield and enantioselectivity. Interestingly the same catalytic salt was found to be active when 1-indanones derivatives were directly employed in the reaction with dibenzoyl peroxide furnishing chiral 1-oxo-2,3-dihydro-1H- inden-2-yl benzoates in high yields and enantioselectivity. Furthermore their treatment with NaBH _4 gives easy access to the corresponding enantioenriched 1,2-diols in high yields and without any loss of stereoselectivity.