p-Toluenesulfonic acid → 1501-32-2

Participants

Reaction Steps

To N-(2-nitrophenyl)-DL-glutamic acid dimethyl ester (XI, EXAMPLE 279, 5.09 g) in methanol (150 ml) is added p-toluenesulfonic acid (0.158 g) and palladium on carbon (10%, 0.495 g). The mixture is shaken under hydrogen at 37 psi for 2 hr; the mixture is then filtered and the filtrate is concentrated to about 70 ml. Additional p-toluenesulfonic acid (0.15 g) is added, and the solution is heated at 60° for 1 hr. After cooling, the solid is collected, washed with methanol, and dried to give the title compound, mp 231°-232°; NMR (CDCl3) 2.65, 4.41, 6.93, 7.14, 8.10 and 8.55 δ.

Provenance & Evidence