Sulfuric Acid → HCID 13144513, compound

Participants

Reaction Steps

0.1 mol of 2-(2-chloroethyl)-2,3,5,8-tetrahydro-1,3-dioxo-1H-1,2,4-triazolo[1,2-a]pyridazine-5-carboxylic acid was dissolved in 500 ml of dioxan or dichloromethane. 12 ml of concentrated sulphuric acid were added and the mixture was then treated with 500 ml of isobutene. After stirring at room temperature for 4 days, the mixture was diluted with water and extracted with ether. The ether extracts were washed with 10% sodium carbonate solution, dried over magnesium sulphate and evaporated to give tert.butyl 2-(2-chloroethyl)-2,3,5,8-tetrahydro-1,3-dioxo-1H-1,2,4-triazolo[1,2-a]pyridazine-5-carboxylate of melting point 87°-88° C.

Provenance & Evidence