Sodium Hydroxide → HCID 13179811, compound

Participants

Reaction Steps

Next, a mixture containing 35.8 g (0.15 moles) of 2,4-dimethoxy-benzenesulfonyl chloride and 56 g (0.45 moles) of sodium sulfite is shaken for 3 hours with 100 g of ice until complete solution is obtained. The solution is maintained alkaline by adding 5% sodium hydroxide (to prevent formation of sulfur dioxide) and kept cold by adding additional ice (higher temperatures may cause hydrolysis of the sulfonyl chloride). At the end of 3 hours unreacted 2,4-dimethoxy-benzenesulfonyl chloride can be filtered off and the filtrate acidified with cold concentrated hydrochloric acid to yield a white crystalline precipitate of 2,4-dimethoxybenzenesulfinic acid, m.p. 89-91° C. (lit. 92° C.). The 2,4-demethoxybenzene-sulfinic acid is suspended in water and an equimolar quantity of sodium carbonate added in small portions to dissolve the sulfinic acid. The condensation of the sodium salt of the sulfinic acid with ortho-dinitrobenzene can be carried out by refluxing equimolar amounts of the two for 4 hours. Upon cooling the mixture is filtered and the solid residue recovered and crystallized using acetic acid to yield white shiny crystals of 2,4-dimethoxy-2'-nitrobiphenyl sulfone having a melting point of from about 157.5° C. to about 158.5° C.

Provenance & Evidence