ethyl ethanesulfonate

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: n-Butyllithium (35.0 mL, 1.6M solution in hexanes) was added dropwise during 25 min to a solution of ethyl ethanesulfonate (6.9 g, 50 mmol) (Synth. Comm. 1985, 15, 1057) in THF (100 mL) at −78° C. The reaction mixture was stirred for 15 min then diethyl chlorophosphate (4.35 ml, 30 mmol) was added dropwise. The solution was stirred at −78° C. for 30 min, allowed to warm to 0° C. and then cooled to −78° C. again. 4-Chlorobenzaldehyde (4.2 g, 30 mmol) in THF (30 mL) was then added dropwise during 15 minutes and the resulting mixture was stirred for 1 h at −78° C. and then allowed to slowly reach RT. Water (10 mL) was added to the mixture and the mixture was concentrated in vacuo. The residue was extracted with diethyl ether and the combined organic extracts were washed with aqueous saturated sodium chloride, dried over magnesium sulfate, filtered and the solvent was evaporated in vacuo. Purification by column chromatography, using a gradient of 10% ethyl acetate/hexanes to 15% ethyl acetate/hexanes as eluent, afforded the title compound (4.5 g, 58%). The solution was stirred at −78° C. for 30 min cooled to −78° C. again the resulting mixture was stirred for 1 h at −78° C. allowed to slowly reach RT the mixture was concentrated in vacuo The residue was extracted with diethyl ether the combined organic extracts were washed with aqueous saturated sodium chloride dried over magnesium sulfate filtered the solvent was evaporated in vacuo Purification by column chromatography