a facile and efficient method for the preparation of 1,1-diacetates of aldehydes is improved. the acidified kaolin with sulfuric acid (2 % w/w) catalyzed 1,1-diacetates formation from aldehydes in solvent-free conditions. both aromatic and aliphatic aldehydes gave high yields (85-95 %) of the corresponding 1, 1-diacetates. advantages of this method are the use of inexpensive and selective catal...