2-Methylpropylenediamine → 3,3-Dimethyl-1lambda~6~,2,5-thiadiazolidine-1,1-dione

Participants

Reaction Steps

To a refluxing solution of sulfamide (27.25 g, 283 mmol) in anhydrous pyridine (300 ml) was added dropwise 1,2-diamino-2-methylpropane (25 g, 283 mmol) over 2 hours. The resulting mixture was refluxed for further 16 hours under nitrogen before the solvent was removed under vacuum. The residue was triturated with hexane and the solid was collected by filtration and purified by flash chromatography (silica gel, dichloromethane-methanol 96:4) to give 36.1 g (85%) of the title compound as a white solid; mp 80°-83° C.; δH (360 MHz, DMSO-d6) 7.08 (1H, br t, --NH--), 6.77 (1H, s, --NH--), 3.04 (2H, d, J=6.9 Hz, --CH2 --), 1.24 (6H, s, --CMe2); m/z (EI) 151 (M+ +1).

Provenance & Evidence