Trichloroacetyl isocyanate → HCID 19892504, compound

Participants

Reaction Conditions

Reaction Steps

To a magnetically-stirred solution of 1-(3-cyclopentyloxy-4-methoxyphenyl)-2-phenyl ethanone oxime (4.51 mmol, 1.48 g) in dry tetrahydrofuran (45 mL) at 0° C. is added trichloroacetyl isocyanate (5.00 mmol, 0.943 mg; 0.596 mL) dropwise over 2 minutes and the resulting solution is allowed to stir as the temperature rises slowly from 0° C. to room temperature overnight. The reaction mixture is then cooled to 0° C. and saturated NH3 /acetonitrile solution (25 mL; prepared by bubbling gaseous ammonia through CH3CN at room temperature for 1 hour) is added dropwise to the reaction mixture. The solution is allowed to stir as it warms slowly from 0° C. to room temperature. After 1.5 hours, the tetrahydrofuran is removed in vacuo and the residue is partitioned between methylene chloride (200 mL) and water (200 mL). The aqueous phase is extracted with ethyl acetate (200 mL) and the combined organics are washed with water (200 mL), dried (Na2SO4), and concentrated in vacuo to afford a mixture of product and oxime (~1:1). The residue is purified via flash chromatography (SiO2 : 1) 2% ethyl acetate/methylene chloride, 2) 5% ethyl acetate/methylene chloride, 3) 7% ethyl acetate/methylene chloride) to give a white solid which is triturated with ether/hexane and dried in vacuo at 50° C. to afford analytically-pure title compound (1.22 mmol, 0.450 g; 27%).

Provenance & Evidence