39185-99-4Relevant articles and documents
Preparation method of N -fluorenylmethoxycarbonyl - L -aspartic -4 -tert-butyl ester
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Paragraph 0013; 0027-0029; 0036-0038, (2021/08/25)
The invention relates to the technical field of organic synthesis, in particular to a preparation method of a fluorenylmethoxycarbonyl - aspartic -4 - tert-butyl ester, which comprises the following specific steps: L - aspartic acid is used as a starting raw material, L - aspartic acid internal anhydride hydrochloride is obtained through dehydration treatment of phosphorus trichloride. L- Aspartic acid ester hydrochloride and ethanol were subjected to alcoholysis to obtain L -aspartate hydrochloride. The transesterification reaction L-aspartate and tert-butyl ester gives L -butyl-1 -ethyl-4 -butyl acrylate. Further hydrolysis L-butyl-1 - ethyl ester -4 - gives L -butyl-4 -tert-butyl ester. The L-aspartate -4 - tert-butyl ester is reacted with the fluorenylmethoxycarbonyl reagent to obtain the target product fluorenylmethoxycarbonyl - aspartic -4 -tert-butyl ester. The preparation method of the fluorenylmethoxycarbonyl - aspartic -4 - tert-butyl ester provided by the invention is safe and environment-friendly in production process and suitable for industrial large-scale production.
Synthesis of novel chiral oxazoline ligands and application in the highly enantioselective diethylzinc addition to N-diphenylphosphinoylimines
Yan, Gexin,Wu, Yong,Lin, Wenqing,Zhang, Xiaomei
, p. 2643 - 2648 (2008/04/05)
Two sets of novel chiral oxazoline ligands were designed and conveniently prepared from readily available l-aspartic acid and evaluated in enantioselective diethylzinc addition to N-diphenylphosphinoyl imines. In the presence of stoichiometric amounts of these ligands, high enantioselectivities (up to 95% ee) and yields (up to 85%) were achieved for several aromatic imines in toluene at room temperature. Furthermore, the effect of the structure of the ligand on the reaction was studied.
Process for isolation of aspartyl dipeptide esters
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, (2008/06/13)
The isolation of certain dipeptide esters, known to be potent sweetening agents, is achieved by selectively extracting, with a suitable alkanol in a heterogeneous system, an aqueous solution containing the dipeptide ester together with a variety of impurities.