boron trifluoride diethyl etherate

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 under N2; soln. of BBr3 (1.05 equiv) in toluene added dropwise at -78 °C to suspn. of (CuMes)5*toluene in toluene; mixt. stirred at -78 °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 under N2; soln. of BBr3 (0.48 equiv) in toluene added dropwise at -78 °C to suspn. of (CuMes)5*toluene in toluene; mixt. allowed to slowly warm to room temp.; mixt. heated to 100 °C for 12 h; after filtration all volatiles removed under high vac.; crude product purified by recrystn. from hexanes at -37 °C; elem. anal.;

in toluene under N2; soln. of MesBBr2 (1.0 equiv) in toluene added to soln. of (CuMes)5*toluene in toluene at room temp.; mixt. heated to 100 °C for3 h; after filtration all volatiles removed under high vac.; crude product purified by recrystn. from hexanes at -37 °C; 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;

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;

in tetrahydrofuran Irradiation (UV/VIS); under Ar; irradn. (254 nm) for 18 h did not gave deposition of Cu; it gave no redn. of Cu(acac)2 at all; the triarylborane was completely recovered;