Cyclopentanone → HCID 86662302, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-bromo-3-[(2,2-difluoroethyl)amino]thiophene -2-carboxamide (150 mg, 0.53 mmol), cyclopentanone (2.0 mL), CSA (12 mg, 0.053 mmol), MgSO4 (100 mg) and DMA (1 mL) was stirred at 110° C. for 20 h. The mixture was poured into saturated aqueous NaHCO3. The organic materials were extracted with EtOAc. The combined extracts were washed with water and brine, dried over Na2SO4 and filtered. After removal of the solvent at reduced pressure, the residue was purified by column chromatography (Purif, silica gel, hexane to 80:20 hexane/EtOAc) to give a brown crystalline solid. A flask was charged with this solid, 1,2-dimethoxyethane (4 mL), tert-butyl 3-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole-1-carboxylate (370 mg, 1.20 mmol), sodium carbonate (120 mg, 2.00 mmol) and water (2 mL). The flask was purged with argon. Then, 1,1′-bis(diphenylphosphino) ferrocenepalladium (II) dichloride dichloromethane adduct (33 mg, 0.040 mmol) was added to the mixture. The flask was purged with argon. After stirring at 100° C. for 2 h, 8 M aqueous NaOH (1.0 mL) was added. After stirring at 100° C. for 30 min, organic materials were extracted with EtOAc. The combined extracts were washed with brine, dried over Na2SO4 and filtered. After removal of the solvent at reduced pressure, the residue was purified by column chromatography (Purif, silica gel, 80:20 hexane/EtOAc to EtOAc), then crystallized from heptanes/EtOAc to give the title compound (29 mg, 16%) as a yellow solid:

Provenance & Evidence