ethyl ether hydrochloride in tetrahydrofuran T=-78 - 20°C;

in toluene under N2 atm. to soln. Me3SiCCSnMe3 in toluene was added C6H4O2BCl in toluene at -78°C, react. mixt. was warmed to room temp. over 7 h and stirred for additional 12 h; solvent was removed in vacuo, residue was purified by distillation;

1.1: n-BuLi / hexane / 2 h / -78 - 20 °C 1.2: 71 percent / hexane / 20 °C 2.1: 67 percent / HCl*OEt2 / tetrahydrofuran / -78 - 20 °C View Scheme