On the synthesis of (S)-α-methylaspartic acid by diastereoselective alkylation of a chiral 2-cyanopropanoate
作者:Carlos Cativiela、Maria D. Díaz-de-Villegas、JoséA. Gálvez、Yolanda Lapeña
DOI:10.1016/s0040-4020(97)00249-4
日期:1997.4
A novel and efficient procedure for the synthesis of optically pure α-methylaspartic acid, based on the diastereoselectivealkylation of (1S,2R,4R)-10-(dicyclohexylsulfamoyl)isobornyl 2-cyanopropanoate with α-halocarbonyl compounds, is described.
Enantiospecific synthesis of amino acids: preparation of (R)- and (S)-α-methylaspartic acid from (S)-tryptophan
作者:Chat-On Chan、David Crich、Swaminathan Natarajan
DOI:10.1016/s0040-4039(00)92648-0
日期:1992.6
The enantiospecificsynthesis of both antipodes of α-methylaspartic acid from (S)-tryptophan is described with the key steps being alkylation of the hexahydropyrroloindole 4, oxidative degradation of indoles and, for the preparation of the (R)-isomer, Barton reductive decarboxylation.
Enantioselective Allylations of Azlactones with Unsymmetrical Acyclic Allyl Esters
作者:Barry M. Trost、Xavier Ariza
DOI:10.1021/ja992754n
日期:1999.11.1
A catalytic asymmetric synthesis of quaternaryamino acids has been developed. The method derives from the asymmetric allylic alkylation (AAA) reaction with chiral palladium catalysts derived from π-allylpalladium chloride dimer and the bis-2-diphenylphosphinobenzamide of R,R-1,2-diaminocyclohexane and related ligands. Highly symmetrical allylating agents such as allyl acetate and 2-methallyl acetate