L-Tryptophan → N-[(phenylmethoxy)carbonyl]-L-tryptophan 1,1-dimethylethyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a suspension of N-[(phenylmethoxy)carbonyl]-L-tryptophan (33.27 g; 98.32 mol) (previously prepared by reacting L-tryptophan with CBZCl, in H2O and 1N NaOH), benzyltriethylammonium chloride (BTEAC) (22.4 g; 98.32 mol) and K2CO3 (176.91 g; 1.28 mol) in dimethylacetamide (750 mL) is added tert-butyl bromide (265 mL; 2.36 mol). The solution is heated to 55° C. and vigorously stirred for 19 hours. The mixture is then cooled to room temperature, diluted with H2O (3L) and then extracted with EtOAc (2×1L). The organic phases are evaporated to dryness to obtain the title product as a pale yellow oil (36 g; 98 mol)

Herkunft & Nachweise