PREPARATION METHODS OF (4S,5R)-SEMI-ESTERS

摘要

The solution pertains to the technical field of organic chemistry, in particular to preparation methods of (4S,5R)-semiesters comprising the enantioselective ring-opening of cyclic acid anhydrides with alcohols under the catalysis of cinchona alkaloid so as to obtain the (4S, 5R)-semiesters. The reaction is carried out in the organic solvent at atmospheric, elevated or reduced pressures, the reaction temperature is -80°C to 25°C, the reaction time is 10 to 80 hours, the overall yield is more than 90 percent, and the ee is more than 98.5 percent. The raw materials of the method of the invention are easy to obtain, the catalyst can be recovered quantitatively, the reaction conditions are mild, and the yield and the stereoselectivity are high. So the methods are suitable for industrial process.