2-Thiopheneboronic acid → HCID 69957093, compound

Participants

Reaction Steps

The 2-bromo-N-[3-chloro-4-(10,11-dihydro-5H-pyrrolo[2,1-c][1,4]benzodiazepine-10-carbonyl)-phenyl]benzamide (1.04 g, 2.0 mmol) and thiophene-2-boronic acid (0.32 g, 2.4 mmol), and barium hydroxide octahydrate (0.88 g, 2.8 mmol) was suspended in ethylene glycol dimethyl ether (28.8 ml) and water (4.8 ml). The heterogeneous mixture was stirred at room temperature and purged with nitrogen for ten minutes before bis(triphenylphosphine) palladium (II) chloride (0.17 g, 0.24 mmol) was added. The reaction was capped with a nitrogen balloon and heated in an oil bath at 70° C. After 20 hours, additional thiophene-2-boronic acid (0.13 g, 1 mmol) was added to the reaction. After 24 hours additional bis(triphenylphosphine)-palladium(II)chloride (84 mg, 0.12 mmol) was added to the reaction flask. The reaction was cooled to room temperature and the mixture was extracted into benzene. The combined organic extracts were washed with brine, dried (MgSO4), filtered and concentrated in vacuo to yield a brown solid (1.42 g). The solid was triturated with ethyl acetate and filtered. The filtrate was purified by flash chromatography using silica gel with hexane-ethyl acetate (1:1) as the mobile phase to afford a pale yellow solid (0.59 g, 56%), which was dried under vacuum at 78° C. for two days, m.p. 132°-136° C. MS (EI),m/z: 523 (M+).

Provenance & Evidence