p-Toluenesulfonic acid → Ethyl 2-((2-aminoethyl)((2-(trimethylsilyl)ethoxy)carbonyl)amino)acetate para-toluene sulphonate

Participants

Reaction Steps

A solution of ethyl 2-((2-((tert-butoxycarbonyl)amino)ethyl)((2-(trimethylsilyl)ethoxy)carbonyl)amino)acetate (intermediate 125, 7.70 g, 19.72 mmol) in Et2O (50 ml) was added to a solution of para-toluene sulphonic acid (3.94 g, 20.70 mmol) in EtOH (50 ml) at room temperature. The rotated solution was then evaporated under a reduced pressure of 270 mbar at room temperature for 40 minutes and then for 1 h at 55° C. To the residue was added EtOH (50 ml), which was again removed by evaporation to give the title compound as a yellow oil. (MS) ESI-MS 291.3 [M+H]+

Provenance & Evidence