反应详情

A stirring solution of (12(b)) (495 mg; 1.5 mmole) in dichloromethane (25 mL) was cooled in an ice bath and DMF (1 drop) and oxalyl chloride (0.175 mL: 2.0 mmole) added dropwise. The solution was stirred at ambient temperature under argon for 4 hours. The dichloromethane and excess oxalyl chloride were removed in vacuo. The residue was azeotroped with toluene (2×15 mL) to give 5-(3,4-dichlorobenzyl-carbamoyl)-thiophene-2-carbonyl-chloride (12(c)) which was used crude in the next step.

1. customThe dichloromethane and excess oxalyl chloride were removed in vacuo
2. customThe residue was azeotroped with toluene (2×15 mL)