Benzo(B)Thiophene-2-Boronic Acid → HCID 59024282, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-bromo-7-iodo-1H-indazole (Preparation #22a, 30.0 g, 92.9 mmol) and thianapthene-2-boronic acid (21.5 g, 120.7 mmol), DME (480 mL), water (48 mL), Na2CO3 (29.5 g, 279 mmol) and tetrakis triphenylphosphine palladium (0) (8.6 g, 7.43 mmol) was heated at about 90° C. in an oil bath under an atmosphere of nitrogen for about 15 hours. The solvent was removed under reduced pressure and the residue was suspended in a mixture of ethyl acetate (600 mL) and water (300 mL). The mixture was stirred for about 30 minutes and the resulting solid was collected by filtration and dried to yield 7-Benzo[b]thiophen-2-yl-5-bromo-1H-indazole (21.4 g, 70%); (DMSO-d6, 400 MHz) δ 13.63 (s, 1H), 8.24 (s, 1H), 8.05-8.09 (m, 3H), 7.92 (d, 1H), 7.65 (s, 1H), 7.16 (m, 2H); RP-HPLC (Table 1, Method e) Rt=2.69 min; m/z: (M−H)− 328.4.

Provenance & Evidence