in toluene T=100°C; 36 h;

in hexane; toluene under N2; soln. of BCl3 (1.05 equiv) in hexanes added dropwise to suspn.of (CuMes)5*toluene in toluene at -78 °C; mixt. stirred at -78 . degree.C for 2 h and then allowed to slowly warm to room temp. overnight; after filtration all volatiles removed under high vac.; crude product purified by distn. under reduced pressure; elem. anal.;

in toluene byproducts: dimesitylene; under N2; soln. of MesBCl2 (1.0 equiv) in toluene added to soln. of (CuMes)5*toluene in toluene at room temp.; mixt. heated to 100 °C for36 h; after filtration all volatiles removed first at room temp and then at 100 °C under high vac.; residue purified by recrystn. from hexanes at -37 °C; elem. anal.;

in toluene under N2; soln. of the borane (1 equiv) in toluene added to soln. of theCu complex in toluene at room temp.; mixt. heated to 100 °C for 36 h; NMR spectroscopy;