Phosphorus oxide (P4O10) → 3,4-Dihydro-8-fluoro-7-methyl-2-oxo-1-benzazepine

Participants

Reaction Steps

To 70 ml of 85% phosphoric acid, 100 g of phosphoric anhydride were added in portions. After the phosphoric anhydride was dissolved thoroughly, 10.0 g of 7-fluoro-6 -methyl-1-tetralone oxime were added to the resulting solution over 20 minutes at an external temperature of 90° C., followed by stirring for 4 hours under the same conditions. After the completion of the reaction, the reaction mixture was poured into ice water. The crystals so precipitated were collected by filtration. The crystals so obtained were recrystallized from chloroform-diethyl ether, whereby 8.3 g of the title compound was obtained.

Provenance & Evidence