RHODIUM-MEDIATED INSERTION OF CF3-SUBSTITUTED CARBENOID INTO O-H - ANEFFICIENT METHOD FOR THE SYNTHESIS OF ALPHA-TRIFLUOROMETHYLATED ALKOXYACETIC AND ARYLOXYACETIC ACID-DERIVATIVES

CF3-substituted diazo compound 2 undergoes a facile rhodium carbenoid mediated O-H insertion reaction with a variety of alcohols and phenols to afford the title compounds in good yield. Use of the title compoun ds as synthetic precursors for other fluorinated molecules is exemplif ied by the transformation of the product 3b, into beta, beta-difluoro- alpha-ketoester 5 and alpha-hydroxyketone 8.