in dichloromethane Ar atm., Schlenk techniques; 1,1'-bis(dicyclohexylphosphino)ferrocene and PdCl2(PhCN)2 in CH2Cl2 stirred for 2 h; addn. of Et2O, mixt. stirred for 5 min, filtration, filtrate concd. and layered with Et2O, crystn. on cooling in freezer; elem. anal.;