Ethyl Acetate → methyl 3-chloro-7-(2,2-dimethylpropionylamino)-10H-9-oxa-1,2-diazaphenanthrene-8-carboxylate

Participants

Reaction Conditions

Reaction Steps

A suspension of methyl 7-(2,2-dimethylpropionylamino)-3-hydroxy-10H-9-oxa-1,2-diazaphenanthrene-8-carboxylate (Intermediate 9, 1.12 g) in phosphoryl chloride (10 mL) was stirred and heated at 95° C. for 45 minutes. After cooling, the mixture was poured into a mixture of ice and ethyl acetate. The organic phase was washed with water and sodium bicarbonate solution, dried (Na2SO4) and filtered. The filtrate was evaporated in vacuo and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 0-15% to give methyl 3-chloro-7-(2,2-dimethylpropionylamino)-10H-9-oxa-1,2-diazaphenanthrene-8-carboxylate (1.02 g) as a light coloured solid.

Provenance & Evidence