Expedient Synthesis of Symmetric Aryl Ketones and of Ambient-Temperature Molten Salts of Imidazole

A short procedure for the synthesis of 2,2-di(3-thienyl)-1,3-dioxolan is described. The route developed is convenient (only two synthetic and one chromatographic steps are required) and efficient (66% overall yield from 3-bromothiophene). This compound was transformed into the ketone, cyclopenta[2,1-b:3′,4′-b′]dithiophen-4-one by a known process. Optimized syntheses of symmetric aryl ketones, 1-alkyl-3-methylimidazolium and 1-alkyl-2-methyl-3-methylimidazolium liquid salts are also reported.