Dimethylmalonic acid → N-(4-methylthiophenyl)-2,2-dimethylmalonamic acid

Reaktionsgleichung

S(Cl)(Cl)=O.[CH3:5][C:6]([CH3:13])([C:10]([OH:12])=[O:11])[C:7](O)=[O:8].[CH3:14][S:15][C:16]1[CH:22]=[CH:21][C:19]([NH2:20])=[CH:18][CH:17]=1>C1COCC1>[CH3:14][S:15][C:16]1[CH:22]=[CH:21][C:19]([NH:20][C:7](=[O:8])[C:6]([CH3:13])([CH3:5])[C:10]([OH:12])=[O:11])=[CH:18][CH:17]=1

Komponenten

Versuchsvorschrift

Thionyl chloride (8.15 g, 5 ml, 0.069 mol) was added to a stirred solution of 2,2-dimethylmalonic acid (7.26 g, 0.055 mol) in dry THF (55 ml). The mixture was heated under reflux for 3 hr. The reaction mixture was cooled to room temperature and 4-methylthioaniline (15.3 g, 0.11 mol) in THF (30 ml) was then added dropwise over 30 mins to the solution. The mixture was stirred at room temperature for 2 hr. The reaction mixture was then concentrated in vacuo and then treated with hydrochloric acid (2N, 100 ml). The product was extracted with ethyl acetate (2×100 ml). The organic extracts were combined, then washed with water (100 ml) and saturated sodium hydrogen carbonate solution (5×80 ml). The organic layer was then acidified with hydrochloric acid (5N, 250 ml) and the resultant white crystalline precipitate was collected by filtration to afford N-(4-methylthiophenyl)-2,2-dimethylmalonamic acid. mp 130-132° C.