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