Boric acid: an efficient and environmentally benign catalyst for transesterification of ethyl acetoacetate

An efficient and environmentally benign boric acid catalyzed protocol for the transesterification of ethyl acetoacetate with a variety of primary and secondary alcohols in good to excellent yields is described. The versatility of this transformation is demonstrated with problematic substrates such as propargyl alcohol and allyl alcohol, which are known to undergo Carroll rearrangement during transesterification.