One-Pot Generation and Conversion of Trichloroacetimidates for the Racemization-Free Allylation and Benzylation of α-Hydroxyesters and the Enantiopure Synthesis of a Chiral Diglycole

O-Allylations and O-benzylations of a-hydroxy esters (3a-3c) are performed without racemization. The reagents applied, O-allyl- and O-benzyltrichloroacetimidate (5a, 5b) are prepared and converted in a one-pot-procedure. After protection by benzylation (S)-(-)-ethyl lactate (3a) is converted by a sequence of carbonyl reduction, alcohol activation, ether formation, and deprotection to the optically active diglycole derivative 1a