TITANIUM SILICATE MOLECULAR-SIEVES (TS-1 AND TS-2) CATALYZED MICHAEL REACTION OF SILYL ENOL ETHERS WITH ALPHA,BETA-UNSATURATED CARBONYL-COMPOUNDS

The Michael addition reaction has been carried out with silyl enol eth er and Michael accepters such as acrylates, and alpha,beta-unsaturated ketones over aluminum-free titanium silicates (TS-1 and TS-2) in the absence of H2O2. The reaction was carried out slightly above room temp erature (40 degrees C) in the presence of dry solvents giving moderate to good yield. The effect of various modified zeolites like RE-Y, La- Y, steamed-Y, Na-Y, VS-1, SnS-1, Zn/ZSM-5 and different solvents has b een studied. The catalytic activity is explained on the basis of ''oxo philic Lewis acidity'' of titanium silicate molecular sieves.