以轴手性的BINOL/H8-BINOL(BINOL为联苯酚)和大位阻的金刚烷酰氯为原料,合成了系列新型手性单齿亚磷酸酯配体,并应用于Cu催化的二乙基锌对环烯酮的不对称1,4-共轭加成反应中.结果表明,配体结构中部分氢化的2,2′-(1,1′-联萘基)亚磷酸酯单元和金刚烷基团,有助于改善反应的对映选择性,对映选择性最高可达79%.
A series of new bulky monophosphite ligands were synthesized from axially chiral BINOL/H8-BINOL(BINOL:1-(2-hydroxynaphthalen-1-yl)naphthalen-2-ol) and highly sterically hindered adamantylcarbonyl chloride.The effectiveness of these ligands was evaluated by the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to cyclic enones with enantioselectivities of up to 79% ee.The results showed that a ligand structure comprising a partially hydrogenated 2,2'-(1,1'-binaphthyl)phosphite scaffold and an adamantyl moiety was effective in improving the enantioselectivity.