Triethylamine → HCID 131710216, compound

Participants

Reaction Conditions

Reaction Steps

15.5 g of Z-Gly-Phe-Gly-OH [manufactured according to J. R. Vaughan & J. A. Eichler, J.Am.Chem.Soc. 75, 5556 (1953)] are dissolved in 100 ml of absolute tetrahydrofurane and 5.3 ml of absolute triethylamine and 4.64 ml of isobutyl chlorocarbonate are added dropwise to the solution cooled to -20°C, whilst stirring, in such a way that the internal temperature does a way that the internal temperature does not exceed -15°C. Thereafter the mixture is allowed to react for 10 minutes at -10°C, is then again cooled to -20°C, and a solution of 7.6 g of H-Pro-OtBu in 30 ml of dimethylformamide is added dropwise whilst stirring, in such a way that the internal temperature does not exceed 0°C. The mixture is allowed to stand for 18 hours at 0°C, the triethylamine hydrochloride is then filtered off and the filtrate is evaporated at 40°C bath temperature. The residue is dissolved in 200 ml of ethyl acetate and the solution is washed with sodium bicarbonate solution, water, 10 % strength tartaric acid solution and water, dried with sodium sulphate and evaporated. The residue is crystallised from ethyl acetate-petroleum ether, melting point 66°- 71°C; [α]D20 = - 45° (c = 1% in chloroform).

Provenance & Evidence