in benzene dropwise addn. of phosphine to Ge compd. soln. with stirring, 0°C; heating to room temp.; stirring, 12h; pptn.; filtration under Ar;

in benzene dropwise addn. of phosphine to soln. of benzile and Ge compd. with stirring, 0°C; heating to room temp.; stirring, 12h; pptn.; filtration under Ar; detn. by NMR;