Oxalyl chloride → HCID 22142198, compound

Participants

Reaction Steps

Into a 100 mL round bottom flask equipped with a reflux condenser, nitrogen inlet and magnetic stirrer is placed 250 mg (0.68 mmol, 1.0 equiv.) of 6-Ethoxy-8-(4-methyl-piperazin-1-yl)-4-oxo-4H-chromene-2-carboxylic acid hydrochloride salt (Reference Example 23d) and 20 mL of methylene chloride. To the stirring suspension is then added 129.5 mg, 164 L (1.02 mmol, 1.5 equiv.) of oxalyl chloride followed by addition of one drop of DMF from a 50 microliter syringe to act as catalyst. The mixture is stirred for 2 hours, then concentrated to dryness on a rotary evaporator under a nitrogen atmosphere, followed by drying under high vacuum. The completeness of the reaction was ascertained by analysis of an aliquot, which was quenched with a THF solution of methylamine, by LC/MS. The crude material was used as obtained in the subsequent amidation reaction.

Provenance & Evidence