反应详情

A solution of 12.0 g of ethyl 6-amino-1-ethyl-1,4-dihydro-7-methoxy-4-oxo-1,8-naphthyridine-3-carboxylate in 120 ml of ethanol and 60 ml of aqueous 42% tetrafluoroboric acid was cooled to 0° C. To the solution kept at 0°-3° C. was added 6.0 g of isoamyl nitrite. The mixture was stirred for 30 minutes at the same temperature, and then diluted with 600 ml of ether to give a precipitate which was collected and washed with ether to give 12.8 g of 3-ethoxycarbonyl-1-ethyl-1,4-dihydro-7-methoxy-4-oxo-1,8-naphthyridine-6-diazonium tetrafluoroborate, decomposing at 142°-147° C.

1. customkept at 0°-3° C.
2. customto give a precipitate which
3. customwas collected
4. washwashed with ether