| 摘要 |
PROBLEM TO BE SOLVED: To produce a new chiral diphosphine compound, useful as a ligand of a transition metal complex, and capable of providing a catalyst for asymmetric synthetic reaction, especially an asymmetric hydrogenating reaction with excellent chemical selectivity and enantio-selectivity. SOLUTION: This diphosphine compound is represented by formula I [R<1> and R<2> are each independently a cycloalkyl, a (substituted)phenyl or a 5-membered heteroaromatic residue], e.g. (-)-((5, 6),(5',6')-bis(methylenedioxy) biphenyl-2,2'-diyl)bis(diphenylphosphine). The exemplified compound is obtained according to a scheme represented by formula II (Ph is phenyl; LDA is lithium diisopropylamide; DMF is dimethylformamide; DBT is dibenzoyltartaric acid). |
