The Asymmetric Synthesis Of The D-prolinamide And Racemic

Prolinamide is a very important cyclo-aminoacid derivatives. As an important pyrrolidine derivative, D-Prolinamide shows its excellent asymmetric source potential both in synthesizing chiral Pharmaceuticals and asymmetric reactions, such as CDDP, TRF, Remoxipride and Neuroleptic. Chiral source technique is the main method to synthesize D-Prolimamide, however, D-Proline is very hard to obtain from nature directly though it can be synthesized from chiral separation which has a very limited yield with 50% at most, so it is very expensive.Basing the economical factor, this paper used asymmetric transformation method to obtain D-proline after using L-Proline as starting material and S-Tartaric acid as chiral separation agent. Then, we got the D-Prolinamide after a series of reactions including protection reaction, amidate and de-protection reaction. Finally, we optimized the whole process.We used benzyl chloroformate and 4-Toluenensulfonyl chloride agent for a good comparability to protect amide of proline. And we discussed the feasibility of the two protection agent from the final results.During the total preparation process, it was inevitable to conduct with the chiral center of prolinamide and the target product would became racemized or even could not be obtained at all. So we also investigated the D-Prolinamide's racemic reactions at different temperature, pH value and reaction time and its decarboxylation mechanism. It should be very valuable in the future industrial production.