Triethylamine → 1-(5-Bromo-4-(4-trifluoromethylthiazol-2-yl)pyridin-2-yl)-3-ethylurea

Participants

Reaction Steps

A suspension of 1-(5-bromo-4-(4-hydroxy-4-(trifluoromethyl)-4,5-dihydrothiazol-2-yl)pyridin-2-yl)-3-ethylurea (Intermediate 7, 175.8 g, 430 mmol) and triethylamine (295 mL, 2.13 mol) in tetrahydrofuran (3 L) was prepared and stirred at room temperature. Methane sulfonyl chloride (106 mL, 1.36 mol) was added dropwise over the course of an hour. This mixture was stirred at room temperature for 6 hours. The solid was collected by filtration, rinsed with tetrahydrofuran (2×500 mL), and the filtrate was retained while the solid was discarded. The combined tetrahydrofuran layers were concentrated to a viscous, yellow semi-solid which was then washed with water (2×500 mL). This solid was further stirred with water (500 mL) for 18 hours, then filtered and dried in the vacuum oven at 50° C. for 12 hours to give 121.8 g (73%) of 1-(5-bromo-4-(4-(trifluoromethyl)thiazol-2-yl)pyridin-2-yl)-3-ethylurea as an off-white solid.

Provenance & Evidence