Synthesis Of Morpholine-2,5-dione Derivatives And Copolymerization With Lactide

In this paper, (3S)-3-[ (benzyloxycarbonyl)-methyl ]-morpholine-2,5-dione(BMMD) wassynthesized using L-aspartic acid, bromine, acetic acid and benzene methanol as rawmaterials firstly. The structure of the products was characterized by FTIR and 1H-NMR. Thebetter synthesis conditions of the products is determined by investigating the factors of pH tothe productivity ofβ-benzyl-N-(bromo-acetyl)-L-aspartic acid ester and the dropping speed tothe productivity of (3S)-3-[ (benzyloxycarbonyl)-methyl ]-morpholine-2,5-dione. The totalproductivity of the reaction can extend to 33% or more through improving the synthesisprocess. Under the same conditions, morpholine-2,5-dione and (3S)-3-[ (benzyloxycarbonyl)–ethyl ]-morpholine-2,5-dione was synthesized from glycine and L-glutamate, respectively,with production rate has improved greatly.Then, (3S)-3-[ (benzyloxycarbonyl)-methyl ]-morpholine-2,5-dione and lactide(LA)were copolymerizated by ring opening reaction, with stannous octoate as catalyst. Thestructure of the copolymers was characterized by FTIR spectroscopy and 1H-NMRspectroscopy. The experiment studied the intrinsic viscosity of polymer at the differentpolymerization temperature, reaction time and the feed ratio.Poly [ ( lactic acid )-co-( glycolic acid ) -alt- (β- ( benzyl - aspartate ) ] was synthesizedsuccessfully, named as poly[ LA-co-(Glc-alt-L-Asp(Bz)) ], The amino acids with multiplefunctional groups-L-aspartic acid in the polylactic acid is introduced into the polylactide. Theprotective group of the polymers is removed by catalytic hydrogenation, PLA is expected toget to the side chain with reactive functional groups that the hydrophilicity will be improved.