新型手性胺膦-铱体系催化芳香酮的不对称转移氢化

Asymmetric Transfer Hydrogenation of Aromatic Ketones Catalyzed by New Chiral Diaminodiphosphine-Iridium(I) Systems

合成了含-CH3取代基的PNNP型手性双胺双膦配体,并采用核磁共振、质谱、红外光谱及圆二色光谱等方法对其进行了表征.在异丙醇溶液中,考察了该配体与[IrHC l2(COD)]2组成的手性胺膦-铱体系对多种芳香酮的不对称转移氢化性能.结果表明,该手性胺膦-铱体系是催化多种芳香酮不对称氢转移氢化的优秀催化剂.在室温下,用该体系催化1,1-二苯基丙酮时,可得到99%的转化率和99%ee的对映选择性.

The chiral PNNP ligands containing -CH3substituents have been synthesized and characterized by NMR, MS, IR and CD spectra. The chiral diaminodiphosphine-iridium （Ⅰ） systems, prepared in situ from [ IrHCl2 （COD） ] 2 and the ligands 1 and 2, have been explored. The catalytic performance was investigaed in the asymmetric transfer hydrogenation of various aromatic ketones in ^1PrOH. The resuhs indicated that the catalytic system acted as an excellent catalyst precursor in asymmetric transfer hydrogenation of various aromatic ketone. When the （R, R）-2/[ IrHCl2 （COD） ] 2 as catalyst was employed for the reduction of the 1,1-diphenylacetone at room tempreture, high activity （99% conversion） and excellent enantioselcctivity （99% ee ） were obtained.