13 g 0 111 mol in 150 ml of anhydrous tetrahydrofuran thf at u2212 60 u00b0 c was added n butyllithium 76 2 ml 0 122 mol 1 6 m solution in hexanes dropwise via syringe after stirring for 30 minutes triisopropyl borate 28 2 ml 0 122 mol was introduced via syringe the resulting mixture was allowed to gradually warm to 0 u00b0 c and then distributed between 1n hydrochloric acid and ethyl acetate 300 ml each the layers were separated and the organic layer was dried over sodium sulfate concentration in vacuo produced a white solid that was triturated from ethyl ether hexanes filtration provided 16 4 g 71 of 6 methoxybenzo b thiophene 2 boronic acid as a white solid mp 200 u00b0 c dec 1 h nmr dmso d 6 d 7 83 s 1h 7 78 d j 8 6 hz 1h 7 51 d j 2 0 hz 1h 6 97 dd j 8 6 2 0 hz 1h 3 82 s 3h fd mass spec 208 to a solution of 6 methoxybenzo b thiophene 2 boronic acid 3 00 g 14 4 mmol in 100 ml of toluene was added 4 methanesulfonyloxy phenylbromide.