Pyridine → N-(2-methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxamide

Participants

Reaction Steps

2-Methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenylamine (7) (1.20 g, 5.16 mmol, 1.0 equiv) and pyridine (0.42 mL, 25.8 mmol) are dissolved in DCM (40 mL) at 0° C. under a nitrogen atmosphere. 4,5,6,7-Tetrahydro-benzo[b]thiophene-2-carbonyl chloride (8) (1.03 g, 5.16 mmol) is then added in portions over 5 min and allowed to react warming to RT over 60 min. All solvent is then removed under reduced pressure, and the resultant oil is reduced from toluene (3×20 mL) to remove residual pyridine. The residue is then dissolved in ethyl acetate and washed with sodium hydroxide (1N, 1×100 mL), then washed with saturated sodium chloride (1×100 mL) and dried over sodium sulfate. The solution is then filtered and concentrated under reduced pressure to give 4,5,6,7-tetrahydro-benzo[b]thiophene-2-carboxylic acid [2-methyl-3-(4,4,5,5-tetramethyl-[1,3,2]diaxaborolan-2-yl)-phenyl]-amide (9) as an off-white solid (1.87 g).

Provenance & Evidence