Synthesis of L-(+)-diethyl tartrate by boric acid

L-(+)-diethyl tartrate is synthesized and the structure of the product is confirmed by IR.The specific rotator power is determined by polari meter and the carbon tetrachloride is taken as solvent,the boric acid as catalysis,L-tartaric acid and ethanol as raw material,the results indicate that the molar ratio of L-tartaric acid to Ethanol is 1∶5;The quantity of carbon tetrachloride is 30 mL;The reaction temperature is 70℃,the quantity of the boric acid is under 2 g,So 96.73% of the etherification rate reached,and 90.07%of the receiving rate reached.