Dicyclohexylcarbodiimide → HCID 13021285, compound

Participants

Reaction Steps

157 g of N-carbobenzoxy-L-phenylalanine in 500 ml methylene chloride and 300 ml absolute diethyl ether is treated at 15°-18° C. with 85.5 g L-proline tert.-butyl ester in 100 ml diethyl ether over 5 minutes, and then with 114 g of dicyclohexylcarbodiimide in 150 ml of diethyl ether over 15 minutes, both additions being at such a rate that the reaction mixture temperature does not rise above 18° C. The resultant mixture is stirred for a further hour at room temperature, and filtered, the solid residue being washed with ether. The filtrate is washed with, in turn, 2N hydrochloric acid, water, potassium bicarbonate, and then water, each washing being extracted with diethyl ether. All the organic phases are combined, dried over sodium sulphate and concentrated to yield an oily residue. The oily residue is taken up in methylene chloride, filtered, concentrated and dried in a high vacuum to yield the heading compound as a yellow oil.

Provenance & Evidence