Diethyl aluminum chloride → (2-bromo-5H-pyrrolo[2,3-b]pyrazin-7-yl)-(1-methyl-cycloheptyl)-methanone

Participants

Reaction Conditions

Reaction Steps

A suspension of 2-bromo-5H-pyrrolo[2,3-b]pyrazine (100 mg, 0.505 mmol) in anhydrous dichloromethane (10 ml) was cooled to 0° C. under N2. Diethyl aluminum chloride (1M in hexanes, 1.50 ml, 1.50 mmol) was added quickly, and the reaction mixture was stirred for 30 minutes. 1-Methyl-cycloheptanecarbonyl chloride (882 mg, 5.05 mmol) was added dropwise, and the reaction mixture was refluxed overnight. The reaction mixture was cooled to 0° C. and quenched with saturated aqueous NaHCO3. The biphasic solution was concentrated, and the remaining aqueous solution was extracted with ethyl acetate. The organic layers were collected, dried over MgSO4, filtered, and concentrated giving a pale brown solid. The residue was purified by silica gel chromatography using 19-74% EtOAc in hexanes as eluant providing 55 mg (32%) of (2-bromo-5H-pyrrolo[2,3-b]pyrazin-7-yl)-(1-methyl-cycloheptyl)-methanone as a white solid. MP 197.7-198.2° C., M+H=336.

Provenance & Evidence