boron tribromide T=-78 - 70°C; Inert atmosphereNeat (no solvent);

n-butyllithium in diethyl ether 0°C, allowing to warm to room temp. after addn. of OHCH2CF3 and n-C4H9Li, stirring for 1 h, recooling to -78°C, addn. of BCl3, molar ratio of C6H5BCl2:OHCH2CF3:n-C4H9Li=1:3:3, stirring overnight;

in neat (no solvent) mixing (-20°C, over 15 min), stirring (room temp., 12 h); pentane addn., fractional distn.;