(Pyridin-4-yl)boronic acid → HCID 18470704, compound

Participants

Reaction Steps

To a stirred suspension of 4-acetyl-2-bromo-3-methyl-5-phenyl-1H-pyrrole (139 mg, 0.50 mmol), 4-pyridylboronic acid (307 mg, 2.5 mmol) in DME (1.5 mL) and saturated aqueous NaHCO3 (0.50 mL) was added Pd(PPh3)2Cl2 (70 mg, 0.10 mmol) under nitrogen. The mixture was heated under reflux for 12 hours. After cooling, the mixture was diluted with ethyl acetate (5 mL) and water (10 mL). The organic layer was separated, and then the aqueous layer was extracted with ethyl acetate (5 mL×2). The combined organic layers were extracted with 1M aqueous HCl (3 mL×2). The combined aqueous layes were neutralized by the addition of 10% aqueous KOH until being pH=8. The whole was extracted with CH2Cl2 (10 mL×3), the combined organic layers were dried over MgSO4, and concentrated in vacuo. The residue was purified by flash chromatography eluting with hexane-ethyl acetate (1:2→EtOAc only) to provide the title product (42 mg, 30% yield) as a colorless solid.

Provenance & Evidence