HCID 86736409, compound → HCID 12909280, compound

Participants

Reaction Steps

20 g (0.073 mole) of the 4H-2-methoxycarbonyl-imidazo-[2,1-c][1,4]-benzoxazine-1-carboxylic acid obtained in Step D were added to a flask provided with a magnetic stirrer and the flask was placed in an oil bath at 175°-80° C. Stirring was continued for about twenty minutes until effervescence ceased and the decarboxylated product thus formed was then dissolved in chloroform and the solution obtained was passed down a short silica column to remove any remaining low Rf impurities. The combined fractions containing methyl 4H-imidazo-[2,1-c][1,4]-benzoxazine-2-carboxylate were then evaported to dryness and ether was added with trituration. The offwhite product was filtered off, washed with a little ether and dried to obtain 14.0g (83% yield) of methyl 4H-imidazo-[2,1-c][1,4]-benzoxazine-2-carboxylate with a melting point of 133°-4° C.

Provenance & Evidence