4-Methylmorpholine → HCID 73933413, compound

Participants

Reaction Steps

To a mixture of Z-aminocaproic acid (i.e. the title A compound) (18.6 g, 0.07), L-phenylalanine methyl ester hydrochloride (16.6 g, 0.077 mol), hydroxybenzotriazole hydrate (10.7 g, 0.07 mol) in 350 mL of dry tetrahydrofuran cooled in an ice bath was added N-methylmorpholine (7.1 g, 0.07 mol) followed by water soluble carbodiimide reagent, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (13.5 g, 0.07 mol). After stirring cold for 4 hours, the reaction was allowed to warm to ambient temperature overnight. The reaction mixture was then concentrated in vacuo and next treated with ethyl acetate (400 mL) and pH 4 phosphate buffer (200 mL). The organic phase was rinsed with saturated aqueous sodium hydrogen carbonate solution until thin layer chromatography showed the absence of Z-aminocaproic acid, then with brine and dried over anhydrous magnesium hydrate. Removal of solvents gave 28 g of crude product. This crude product was absorbed onto Baker silica gel (50 g), then flash chromatographed on Merck silica gel (400 g) eluting with 1:1 ethyl acetate:hexane. Collection of the product, eluted in yellow colored fractions, gave 23.3 g of the title B compound as a solid, m.p. 83°-85° C.

Provenance & Evidence