A New Highly Active Diphosphane-Palladium(II) Complex as a Catalyst Precursor for the Heck Reaction
作者:Sven Sjövall、Maria H. Johansson、Carlaxel Andersson
DOI:10.1002/1099-0682(200111)2001:11<2907::aid-ejic2907>3.0.co;2-7
日期:2001.11
The new diphosphane ligand cis-1,3-bis[(diphenylphosphanyl)methyl]cyclohexane (4) has been prepared and has allowed the synthesis of the palladium complex cis-[Pd(4)(CO2CF3)2] (6). To obtain cis complexation of the diphosphane in 6 the cyclohexane skeleton adopts a chair conformation with a diaxial orientation of the substituents, a structure that has been verified by an X-ray structure determination
新的二膦配体顺-1,3-双[(二苯基膦基)甲基]环己烷 (4) 已经制备完成,并允许合成钯配合物顺-[Pd(4)(CO2CF3)2] (6)。为了在 6 中获得双膦的顺式络合,环己烷骨架采用椅式构象,取代基具有双轴取向,这种结构已通过 X 射线结构测定验证。该复合物以高产率有效地催化碘苯和溴苯的乙烯基化。对于最佳反应,丙烯酸甲酯和碘苯的产率 > 98%,平均周转频率为 11 760 h-1,周转数为 1 176 000。