Oxalyl chloride → 3-[5-(2-Fluorophenyl)-[1,2,4]oxadiazol-3-yl]benzoyl isocyanate

Participants

Reaction Conditions

Reaction Steps

Oxalyl chloride (2.5 ml, 28.2 mmol, 2.0 eq.) is then added dropwise under N2 to a suspension of 3-[5-(2-fluorophenyl)-[1,2,4]oxadiazol-3-yl]benzamide (Compound A3, 4.0 g, 14.1 mmol) in anhydrous dichloromethane (20 mL) cooled to 0° C. The mixture is slowly heated to reflux and stirred for an additional 6 h. The solvent is removed on a rotary evaporator. The residue is azeotroped with anhydrous dichloromethane (20 mL) and dried under high vacuum for two hours to give 3-[5-(2-fluorophenyl)-[1,2,4]oxadiazol-3-yl]benzoyl isocyanate (Compound A4) as a tan solid 4.12 g (95%) which may be used immediately without further purification.

Provenance & Evidence