Hydrazine hydrate (1:1) → HCID 12687089, compound

Participants

Reaction Steps

The mixture of 1.0 g of 9carboxy-10,11-dihydro-11-oxodibenzo[b,f]thiepin, 1.0 g of hydrazine hydrate and 30 ml of ethanol was heated under reflux on water bath for 4 hours. The reaction mixture was concentrated to about 15 ml to separate crystals on cooling, which were collected by filtration. They were added to the mixture of 1.0 g of sodium hydroxide and 20 ml of diethylene glycal and the resulting mixture was heated with stirring at 190°-200° C. for 2 hours. After cooling, 300 ml of water was added to the mixture, which was extracted with diethyl ether. The aqueous layer was acidified with conc. hydrochloric acid and extracted with chloroform, and the solvent was evaporated therefrom. The thus obtained residue was chromatographed over silica gel and eluted with benzene-ethyl acetate (1:1), and there was obtained 0.4 g of 9-carboxy-10,11-dihydrodibenzo[b,f]thiepin as yellow prismatic crystals having a melting point of 186°-187° C.

Provenance & Evidence