C2-Symmetric bicyclo[3.3.1]nona-2,6-diene and bicyclo[3.3.2]deca-2,6-diene: new chiral diene ligands based on the 1,5-cyclooctadiene framework
作者:Yusuke Otomaru、Asato Kina、Ryo Shintani、Tamio Hayashi
DOI:10.1016/j.tetasy.2005.02.022
日期:2005.5
As a new type of C2-symmetric chiral diene ligands, which coordinate to a metal by their 1,5-cyclooctadiene framework, we prepared 2,6-disubstituted bicyclo[3.3.1]nona-2,6-diene (bnd*) and bicyclo[3.3.2]deca-2,6-diene (bdd*), and examined their catalytic activity and enantioselectivity for rhodium-catalyzed asymmetric 1,4-addition to α,β-unsaturated ketones and 1,2-addition to N-sulfonylimines. High
作为一种新型的C 2对称手性二烯配体,它们通过其1,5-环辛二烯骨架与金属配位,我们制备了2,6-二取代的双环[3.3.1] nona-2,6-diene(bnd * )和双环[3.3.2] deca-2,6-diene(bdd *),并研究了它们对铑催化的α,β-不饱和酮不对称1,4-加成和1,2-加成的催化活性和对映选择性。为N-磺酰亚胺。在4-氯苯甲醛的N-甲苯磺酸和N -4-硝基苯磺酰亚胺中加入苯基环硼氧烷后,可以观察到Ph-bnd *配体的高对映选择性,从而得到高对映体过量(98-99%ee)的苯基(4-氯苯基)甲胺。