Conversion of lactides into ethyl lactates and value-added products

This Letter describes an attractive and efficient method for Mg(OR)2-mediated lactide alcoholysis. The catalysts were generated in situ from di-n-butylmagnesium and ROH to prevent aggregation of Mg(OR)2. The reaction of ROH [R = Me, Et, RCO2(Me)CH] with lactide initially yielded the ring-opened product HO[CH(CH3)CO]nOR (n = 2 or 3). The complete consumption of lactide caused the reaction to proceed further, giving environmentally friendly lactic acid esters in excellent yields under ambient conditions.