4,7-Dibromobenzo[c]-1,2,5-thiadiazole (1.00 g, 3.41 mmol) and 3-hexylthiophene-2-boronic acid pinacol ester (2.10 g, 7.14 mmol) were placed in a 100 mL 3-neck round bottom flask which was flushed with N2 gas for 5 minutes. Dimethoxyethane (20 mL) and water (30 mL) were added and the mixture was purged with N2 gas for 30 minutes. Sodium carbonate (4.23 g, 34.1 mmol) and catalyst Pd(PPh3)4 (0.430 g, 0.372 mmol) were added and the mixture was heated to 100° C. and stirred for 12 hours. The mixture was extracted into hexanes and passed through a silica column, by eluting first with hexanes (200 mL) and then eluting the product with a solution of 5% EtOAc in hexanes (200 mL). The procedure afforded 1.59 g of vibrant orange, 4,7-bis(3-hexylthiophen-2-yl)benzo[c][1,2,5]thiadiazole (Formula 2) in 99% yield.
