A Convenient Asymmetric Synthesis of the Unnatural Amino Acid 2,6-Dimethyl-L-tyrosine
作者:John H. Dygos、Edward E. Yonan、Mike G. Scaros、Owen J. Goodmonson、Daniel P. Getman、Roy A. Periana、Gary R. Beck
DOI:10.1055/s-1992-26212
日期:——
The title compound was prepared in high optical purity by a five-step synthesis from 3,5-dimethylphenol on a kilogram scale. The key steps were a modified palladium-catalyzed coupling of an aryl iodide with methyl 2-acetamidoacrylate and hydrogenation of the resulting sterically hindered dehydroamino acid 4 using [Rh(1,5-COD)- (R,R-DIPAMP)]BF4 as catalyst.
该标题化合物通过五步合成法从3,5-二甲基酚制备而成,光学纯度较高,规模达到公斤级。关键步骤是对芳基碘化物与甲基2-乙酰氨基丙烯酸酯进行改进的钯催化偶联,以及使用[Rh(1,5-COD)-(R,R-DIPAMP)]BF4作为催化剂对生成的立体位阻去氨基酸4进行氢化。