Propamine → N-(p-nitrobenzyloxycarbonyl)-1-amino-2-propanethiol

Participants

Reaction Steps

A solution of p-nitrobenzyl chloroformate (0.95 g, 4.41 mmol) in Et2O (30 ml) was added dropwise over 45 min. to an ice-cold, stirring mixture of 1-amino-2-propanethiol (0.504 g, 3.94 mmol) in Et2O (100 ml), H2O (11 ml), and 10% aqueous NaHCO3 (10 ml). The resulting mixture was stirred an additional 80 min. at 0°-5°, and then separated into two phases. The organic portion was washed with cold 0.025N HCl (30 ml) and brine (20 ml), dried with MgSO4, filtered, and concentrated under vacuum to a yellow oil (1.28 g). The crude product was purified by preparative TLC on silica gel GF using 20:1 CH2Cl2 -EtOAc as developing solvent to afford an off-white solid (1.00 g). Recrystallization of the chromatographed product from Et2O-petroleum ether gave compound (A3) (0.183 g) as a cream colored solid: mp 54°- 56.5°.

Provenance & Evidence