A direct intramolecular asymmetric catalytic aldol cyclodehydration of meso-3,4-disubstituted-1,6-dialdehydes
作者:Vanya B. Kurteva、Carlos A.M. Afonso
DOI:10.1016/j.tet.2004.10.034
日期:2005.1
The intramolecular asymmetric catalytic aldol cyclodehydration of 1,6-dialdehydes to the corresponding cyclopentene carbaldehydes was accomplished for the first time on the cases of meso-3,4-disubstituted hexanedials. It was found that the presence of a hydroxyl group in the catalyst's molecule seems to be crucial to reach stereocontrol. The chiral centre, bearing the carboxylate functionality, in hydroxy
在内消旋-3,4-二取代的己二醛的情况下,首次完成了1,6-二醛分子内不对称催化醛醇缩合反应生成相应的环戊烯甲醛。发现在催化剂分子中羟基的存在似乎对于达到立体控制至关重要。羟基氨基酸中带有羧酸盐官能团的手性中心控制最终产物的立体化学。对于氨基醇,其中不存在羧酸酯官能团,与羟基连接的碳的构型似乎是关键。另外,已经观察到手性膦和亚磷酸酯是该环脱水的有效催化剂,但是没有诱导立体控制。