Toluene → HCID 66611755, compound

Participants

Reaction Steps

A mixture of [4-(thiophene-2-carbonyl)-[2,1,3]thiadiazol-3-yl]-thiophen-2-yl-methanone (1.7 g, 6 mmol), anhydrous toluene (70 cm3) and Lawesson's reagent (3.8 g, 9.5 mmol) is stirred at room temperature for 2 hours. But-2-ynedioic acid bis-(2-ethyl-hexyl)ester (3.4 g, 10 mmol) is then added and the reaction mixture heated at reflux for 17 hours. Acetone (50 cm3) is added, the mixture pre-absorbed onto silica and purified by column chromatography (40-60 petrol:ethyl acetate; 1:0 to 3:1) to give 4,7-di-thiophen-2-yl-benzo[2,1,3]thiadiazole-5,6-dicarboxylic acid bis-(2-ethyl-hexyl)ester as a yellow/green oil (380 mg, 11%). 1H NMR (300 MHz, CDCl3) 0.71-0.99 (12H, m, CH3), 1.03-1.47 (16H, m, CH2), 1.50-1.75 (2H, m, CH), 3.94-4.15 (4H, m, OCH2), 7.18 (2H, dd, ArH, J 3.6, 5.0), 7.41 (2H, dd, ArH, J 1.2, 3.6), 7.58 (2H, dd, ArH, J 1.2, 5.0); 13C NMR (300 MHz, CDCl3) 10.9, 14.1, 23.0, 23.3, 28.9, 30.0, 38.4, 68.9, 126.0, 127.3, 128.7, 129.6, 132.8, 135.3, 153.7, 167.9.

Provenance & Evidence