Dimethylformamide → 8-bromo-4H-thieno[3,2-c]chromene-2-carbonyl chloride

Participants

Reaction Steps

To a suspension of 8-bromo-4H-thieno[3,2-c]chromene-2-carboxylic acid 3bp (1.50 g, 4.82 mmol, 1 equiv) in dichloromethane (45 mL) at 24° C. was sequentially added oxalyl chloride (3.1 mL, 6.3 mmol, 1.3 equiv, 2.0 M in dichloromethane) and N,N-dimethylformamide (56 μL, 0.72 mmol, 0.15 equiv), as in General Procedure B. After 2 hr, the clear yellow solution was concentrated in vacuo (˜20 mm Hg) to afford crude 4bp.

Provenance & Evidence