Water → 1-(2-Chloro-6-methylphenyl)-3-cyclobutyltetrahydro-2(1H)-pyrimidinethione

Participants

Reaction Steps

To a solution of the diamine of Step A (3.28 g) in dry chloroform (48 mL) was added dropwise under nitrogen at 0° C. triethylamine (3.62 mL). Thiophosgene (1.49 mL) was then added dropwise via syringe and the mixture was stirred in the cold for another 15 minutes. Stirring was continued at room temperature for 1.5 hours, water was added and the the pH was adjusted to 8 with triethylamine. The aqueous layer was further extracted with dichloromethane and the combined extracts were washed with 20% aqueous sodium chloride, dried over anhydrous potasium carbonate and evaporated to dryness. The residue was dissolved in dichloromethane and absorbed onto a column of Merck-60 flash silica gel. Elution with hexane-ethyl acetate 9:1 provided the title compound (3.1 g, 81%) which was further triturated and sonicated with hexane and hexane-ether. The off-white solid was collected, washed with hexane and dried (2.69 g, 75.3%), m.p. 89-91° C.

Provenance & Evidence