A Novel Generation of Coupling Reagents. Enantiodifferentiating Coupling Reagents Prepared in Situ from 2-Chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and Chiral Tertiary Amines
作者:Zbigniew J. Kamiński、Beata Kolesińska、Janina E. Kamińska、Józef Góra
DOI:10.1021/jo0101499
日期:2001.9.1
enantiomeric enrichment depend on the structures of the amine and carboxylic acid. Calculated Kagan enantioselectivity parameters (s) are in the range 1.6-195. Chiral triazinylammonium chlorides formed in situ from CDMT and chiral tertiary amines are postulated as reactive intermediates involved in the process of enantioselective activation of N-protected amino acids.
在手性叔胺(例如士的宁,马钱子碱和斯巴丁胺)存在下,通过2-氯-4,6-二甲氧基-1,3,5-三嗪(CDMT)将外消旋的N-保护的氨基酸与氨基成分偶联对映选择性地得到合适的酰胺或二肽,产率为69-85%。优选的对映异构体和对映异构体富集的构型取决于胺和羧酸的结构。计算的Kagan对映选择性参数在1.6-195的范围内。由CDMT和手性叔胺原位形成的手性三嗪基氯化铵被假定为反应性中间体,参与N保护氨基酸的对映选择性活化过程。