手性羰基铁体系催化酮的不对称氢转移氢化

手性羰基铁络合物很少被用于芳香酮的不对称氢转移氢化.利用不同的羰基铁络合物与手性双胺双膦配体现场络合,形成手性胺膦铁催化体系.考察了它们对多种芳香酮的不对称氢转移催化氢化性能.结果表明,三核的手性胺膦铁簇合物是催化芳香酮不对称氢转移氢化的较好体系.当用三核的铁簇合物Et₃NH]⁺HFe₃(CO)₁₁]^-体系催化1,1-二苯基丙酮的氢化时,最高可获得98%的对映选择性.通过现场红外光谱测定,揣测羰基铁簇合物Fe₃(CO)₁₂在催化反应过程中保持三核的簇合物的簇骼不变.

Asymmetric Transfer Hydrogenation of Ketones Catalyzed by Chiral Carbonyl Iron Systems

Chiral carbonyl iron systems have seldom been used in asymmetric transfer hydrogenation of aromatic ketones. In this study, new chiral iron catalytic systems were synthesized in situ from different carbonyl iron complexes with chiral diaminodiphosphine ligands, respectively. These catalytic systems have been used for the asymmetric transfer hydrogenation of various aromatic ketones under mild conditions. The results indicated that trinuclear iron complexes were the best systems for the reactions. When the Et 3NH]+HFe 3(CO) 11]- as catalyst was used for asymmetric reduction of 1,1-diphenylacetone, high enantioselectivity up to 98% was achieved. Monitoring the reaction in situ by infrared spectroscopy, it could be conjectured that the carbonyl iron cluster Fe 3(CO) 12 kept its trinuclear skeleton unchanged during the catalytic reaction.