Oxalyl chloride → 2-(4-Fluorophenyl)acetyl isocyanate

Participants

Reaction Conditions

Reaction Steps

To a solution/suspension of 4-fluorophenylacetamide (77 mg, 0.50 mmol, see generally, J. Med. Chem. 2003, 46, 4333-4341, the disclosure of which is herein incorporated by referene) in dichloroethane (2 mL) was added oxalyl chloride (0.175 mL, 2.00 mmol). The reaction was heated at 80° C. for 24 h and then 70° C. for two days. By this time, most of the solids had dissolved and the reaction was yellow. LC/MS analysis found a peak with a molecular weight of 211 corresponding to methyl 2-(4-fluorophenyl)acetylcarbamate, resulting from quenching of the isocyanate with methanol. The reaction was concentrated in vacuo to give a yellow slurry. The slurry was redissolved in dichloroethane (2 mL) and again concentrated in vacuo. The resulting residue was redissolved again in dichloroethane (2 mL) to give a 0.25 M solution of 2-(4-fluorophenyl)acetyl isocyanate in dichloroethane, which was used directly in subsequent reactions.

Provenance & Evidence