Dicyclohexylcarbodiimide → HCID 13605234, compound

Participants

Reaction Conditions

Reaction Steps

554 g of N-formyl-p-fluoro-L-phenylalanyl-m-di-(2-chloroethyl)amino-L-phenylalanine are dissolved in 4.5 liters of dimethyl formamide (DMF). The solution is heated slowly for the dissolution step and then cooled to 15° C. While stirring add: 172 g of N-hydroxysuccinimide+225 g of dicyclohexylcarbodiimide+1,235 g-moles of L-methionine ethyl-ester dissolved in DMF. After 16 hours of stirring at room temperature, the precipitated dicylcohexylurea is removed and to the stirred filtrate 18 liters of a mixture of water and ice are added. The white precipitate is filtered, washed with water and completely dried under vacuum. Yield: 710 g (97.2%); m.p.=180°-182° C.; [α]D20 =-7.0°±1° (c=2, DMF).

Provenance & Evidence