Sulfuric Acid → HCID 178470440, compound

Participants

Reaction Steps

A solution of ethyl 6-ethyl-4-hydroxycinnolin-3-yl carboxylate (5.0 g.) in concentrated sulphuric acid (30 ml.) was stirred at 10° C. as chromium trioxide (6.0 g.) was added. The solution was stirred at room temperature for 5 hours and then was poured onto cracked ice. The resulting aqueous solution was extracted with ethyl acetate (4 × 250 ml.), and the combined extracts were shaken with excess sodium bisulphite solution to extract ketonic material as the bisulphite compound. The aqueous bisulphite solution was washed with ethyl acetate (2 × 250 ml.), and then treated with excess 40% v/v formaldehyde in water and sodium bicarbonate solution. The aqueous solution was extracted with ethyl acetate (3 × 250 ml.) and the combined extracts were dried (MgSO4), and filtered. Evaporation of the filtrate yielded a solid residue which on recrystallisation from a mixture of ethanol and ether gave ethyl 6-acetyl-4-hydroxycinnolin-3-yl carboxylate, m.p. 250°-252° C.

Provenance & Evidence