Step E: Preparation of 4-chloroquinazolin-6-ol: 4-chloroquinazolin-6-yl acetate (10.0 g, 44.9 mmol) was dissolved in a methanol solution of ammonia (200 mL, 7N), and the reaction was stirred for 1 hour at room temperature. Upon completion of the reaction, the reaction mixture was concentrated under reduced pressure to about 3 mL, and the residue was ground with ether to precipitate a tan solid which was collected by filtration and dried to give 4-chloroquinazolin-6-ol (6.50 g, 80% yield).
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