Triethylamine → HCID 131710209, compound

Participants

Reaction Steps

27.0 g (90 mmols) of Z-Phe-OH are dissolved in 250 ml of absolute tetrahydrofurane together with 12.5 ml (90 mmols) of triethylamine, and cooled. 14.7 ml (112 mmols) of chlorocarbonic acid isobutyl ester are added dropwise at -18°C and the mixture is stirred for one-half an hour at <-10°C. 18.1 g of H-Ser(tBu)-OCH3 hydrochloride (85.5 mmols) in a finely powdered form are now added to the white suspension (triethylamine hydrochloride), the mixture is diluted with 350 ml of tetrahydrofurane, and 15.0 m (108 mmols) of triethylamine in 100 ml of tetrahydrofurane are then added dropwise. The mixture is stirred for a further 3 hours at about -10°C and then overnight at room temperature. The suspension is then concentrated to about 250 ml in vacuo, taken up in a large amount of ethyl acetate and extracted by shaking with dilute citric acid solution (3 × 200 ml), dilute sodium carbonate solution (3 × 200 ml) and saturated sodium chloride solution (5 × 200 ml), dried over sodium sulphate and evaporated. The crude product is dissolved in 200 ml of ethyl acetate-hexane (1 : 1). White husks crystallise out of the solution on cooling and these are isolated and dried. The product melts at 92.5°- 94°C. [α]D20 = 3° ± 0.5° (c = 2.2 % in methanol).

Provenance & Evidence