Hydrochloric Acid → HCID 86750448, compound

Participants

Reaction Conditions

Reaction Steps

A solution containing 10.0 g (0.036 moles) of 6-acetoxy-3,4-dihydro-2-ethyl-2-hydroxy-5,7,8-trimethyl-2H-1-benzopyran in 100 ml of benzene and 30 ml of dimethylsulfoxide is rapidly dripped, under nitrogen atmosphere, into a suspension containing 1.0 g (0.040 moles) of 97% sodium hydride in 50 ml of dimethylsulfoxide. The solution, after 60 minutes, is cooled to 5° C. and added, by slow dripping, to 50 ml of benzene containing 8.3 g (0.040 moles) of ethyl 5-bromovalerate, while keeping a temperature lower than 25° C. After 24 hours the reaction mixture is diluted with ethyl ether and water, acidified with a 10% aqueous solution of hydrochloric acid and the crude product is recovered by evaporating the organic layer. The pure product, 9.06 g with a yield of 62%, obtained in form of a thick oil by chromatography on a column of silica gel with eluent methylene chloride-ethyl ether in 96:4 ratio, shows the following chemical-physical characteristics:

Provenance & Evidence