4-Nitrophenol → Z-Phe-ONp

Participants

Reaction Steps

A solution of 6.0 g (20 mM) N-carbobenzoxy-L-phenylalanine, 3.3 g (24 mM) p-nitrophenol, and 1.6 g (24 mM) isopropyl isonitrile in 50 ml ethyl acetate was held at 60°C for 40 hours, and then evaporated. The residue was dissolved in ethanol, and the solution stored in a refrigerator until crystals formed. The crystals were filtered out, washed with petroleum ether, and dried. 4.5 g N-Carbobenzoxy-L-phenylalanine p-nitrophenyl ester was obtained (53% yield). M.P. 125.5° - 127°C. [α]D25 = -8.0° (C = 2.2, in chloroform).

Provenance & Evidence