Dichloromethane → N,N'-Dicyclohexylurea

Participants

Reaction Conditions

Reaction Steps

To a solution of a.2.5. g (7.68 mmol) portion of the product of Example 26 in 40 ml of anhydrous dichloromethane 4.75 g (23 mmol) of dicyclohexylcarbodiimide and 2.88 g (23 mmol) of n-valeric acid were added and the reaction mixture was maintained at 25° C. under intermittent stirring for 24 hours. Then the N,N'-dicyclohexylurea formed as by-product was filtered, the filtrate was evaporated under reduced pressure, the residue was mixed with 2×40 ml of distilled water, decanted and the wet product was left to solidify under 50 ml of 50% ethanol. The solid compound was filtered, washed with 2×10 ml of 50% ethanol and dried at 80° C. The raw product obtained was recrystallized from 24 ml of ethanol and the crystals were dried at 100° C. to yield 2.20 g (70%) of the aimed product as a yellow powder, m.p.: 145°-147° C.

Provenance & Evidence