... We also investigated the versatility of this methodology in the synthesis of the non-symmetrically 5,5 ... 4-methylene-1,3-oxazolidinones 13 and 14 (Scheme 4). Compound 13 was synthesized in 95 ... C) for a longer reaction time (72 h), leading to a mixture of 14a/14b (9:91) (Scheme ...