Benzocaine → HCID 23457806, compound

Participants

Reaction Steps

Ten grams (43.8 m moles) 3-hydroxypentadecane and 4.9 g. (1.1 eq) triethylamine in 250 ml. methylene chloride is cooled to -10° C. in a dry ice-acetone bath. To the stirred solution is dropwise added 5.7 g. (1.1 eq) methanesulfonyl chloride in 10 ml. methylene chloride at a rate such that the reaction temperature does not exceed -5° C. After addition is complete, the solution is warmed to room temperature and washed in sequence with 100 ml. of the following ice-cold solutions: water, 10% hydrochloric acid, saturated sodium bicarbonate, and brine. The methylene chloride is dried and evaporated to a viscous, orange oil. Pentadecane-3-methanesulfonate (13.4 g. 43.7 m moles) and 14.4 g. (2 eq) ethyl 4-aminobenzoate in 75 ml. hexamethylphosphoramide is stirred at 120° C. for 18 hours. The cooled solution is diluted with 150 ml. water, the precipitate is filtered, washed with 150 ml. 50% aqueous ethanol and dried. Crystallization from ethanol and then from acetonitrile yields the product as a white solid.

Provenance & Evidence