A solution of (2-chloro-3-hydroxymethylphenoxy)acetic acid methyl ester (1.94 g, 8.41 mmol) in tetrahydrofuran was cooled to −78° C., treated with potassium bis(trimethylsilyl)amide (10.1 mmol), and allowed to stir at −78° C. for about an hour. A solution of diphenylcarbamyl chloride (2.92 g, 12.6 mmol) in tetrahydrofuran was added dropwise, and the resulting mixture was allowed to warm to room temperature and stirred overnight. The mixture was quenched with water, diluted with diethyl ether, and the layers were separated. The aqueous layer was extracted twice more with diethyl ether. The combined organic extracts were dried over sodium sulfate and concentrated in vacuo. Purification of the residue by silica gel flash chromatography, eluting with hexane/acetone (4:1), gave {2-chloro-3-[(diphenyl-carbamoyloxy)methyl]phenoxy}acetic acid methyl ester as a white crystalline solid (1.72g, 48.0%).
