Dichloromethane → HCID 53831084, compound

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Reaction Steps

7.1 g of the crude 4-[N-(2-isopropoxyethyl)-N-tert-butoxycarbonylaminomethyl]benzoic acid ethyl ester are dissolved in 70 ml of methylene chloride, and 40 ml of trifluoroacetic acid are added. The clear solution is left to stand overnight at room temperature and then concentrated by evaporation. The residue is taken up in methylene chloride, washed with aqueous ammonia solution (pH>9) and concentrated by evaporation. The oily/crystalline residue is dissolved in 50 ml of ethanol, and 50 ml of 2N sodium hydroxide solution are added. After stirring for 2 hours at 60°-65°, the solution is concentrated by evaporation and the residue is adjusted to pH 1 with water and 2N hydrochloric acid. The solution immediately becomes extremely cloudy and after about 5 minutes a precipitate forms. The mixture is concentrated by evaporation and the residue is heated briefly with 100 ml of ethanol. The solution is dried with magnesium sulfate, filtered over Hyflo and concentrated by evaporation. The crude crystalline material is suspended in 80 ml of tetrahydrofuran, and 3.2 g of chloroacetyl chloride are added. The suspension is stirred at room temperature for 14 hours, then concentrated to dryness by evaporation. The residue is dissolved in methylene chloride, washed with diluted hydrochloric acid, dried and concentrated by evaporation. Sticky, sparingly soluble crystals are obtained corresponding to 4-[N-(2-isopropoxyethyl)-N-chloroacetylaminomethyl]-benzoic acid.

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