in tetrahydrofuran under N2, to stainless bomb added Mn complex, 1,1-diphenylethylene and THF, bomb sealed and heated to 110°C for 3 d; cooled, solvent removed under vac.;

carbon monoxide in tetrahydrofuran under N2, THF soln. of Mn complex cooled to -78°C, flushed with CO for 10 min, 1.3 equiv LiBHEt3 added dropwise with stirring under CO, soln. stirred for 10 min at -78°C, slowly warmed to room temp., stirred under CO for 2 h; not isolated, detected by IR;