p-Toluenesulfonic acid → HCID 66743287, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-amino-5-bromothiophene-2-carboxamide (221 mg, 1 mmol), PTSA (9.5 mg, 0.050 mmol), cyclohexanone (2.94 g, 30.0 mmol) and acetic acid (2 mL) was stirred at 90° C. for 2 h. Then, the mixture was poured into saturated aqueous NaHCO3 (100 mL). Extraction with EtOAc (100 mL), washing with brine, drying over MgSO4, filtration and concentration under reduced pressure gave a yellow solid. This residue was mixed with 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (582 mg, 3.00 mmol), sodium carbonate (530 mg, 5.00 mmol), 1,2-dimethoxyethane (2 mL) and water (2 mL). The mixture was purged with argon. Then, 1,1′-bis(diphenylphosphino) ferrocenepalladium (II) dichloride dichloromethane adduct (82 mg, 0.100 mmol) was added, and the mixture was purged with argon again. This mixture was refluxed overnight. Then, the mixture was poured into saturated aqueous NaHCO3 (200 mL) and EtOAc (200 mL). After shaking, the insoluble materials were filtered off. From the filtrate, the organic layer was collected, washed with brine, dried over MgSO4, filtered and concentrated in vacuo. This residue was purified by column chromatography (Purif, silica gel, EtOAc to 90:10 EtOAc/MeOH) to afford a yellow solid (86 mg). This solid was triturated with EtOAc/hexane and collected by filtration to afford the title compound (78.7 mg, 27%) as a yellow solid:

Provenance & Evidence