反应详情

A solution of 2-amino-3-bromo-N-ethyl-4-fluorobenzamide (512a, 2.00 g, 7.66 mmol) and triphosgene (Aldrich; 0.796 g, 2.68 mmol) in toluene (80 mL) was heated at 110° C. for 18 h (water-cooled reflux condenser attached to flask). The reaction mixture was then cooled to RT and concentrated in vacuo to give 8-bromo-3-ethyl-7-fluoroquinazoline-2,4(1H,3H)-dione (2.238 g, 7.80 mmol) as a light-yellow solid: m/z (ESI, +ve) 286.9/288.8 (M+H)+. This material was used directly in the subsequent transformation.

1. concentrationconcentrated in vacuo