C4H9Li; HN(CH(CH3)2)2 in tetrahydrofuran addn. of BuLi to amine deriv. in THF at -78°C for 45 min, warmingto 0°C for 10 min, addn. to boron compd. in THF at -78°C, stirring for 30 min, addn. of bromide deriv., keeping at -78°C f or 15 min, warming to 0°C; addn. of satd. aq. NH4Cl, extn. (ethyl acetate), washing with brine, drying over Na2SO4, chromy. (silica gel, 0-20percent ethyl acetate in hexanes), NMR and MS;