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1.3 g (54 mmol) of magnesium turnings, a catalytic amount of iodine, and 50 mL of dry THF was mixed in a flask and heated to slight reflux under nitrogen. A solution of 2-octyldodecyl bromide (18.1 g, 50 mmol) and 25 mL of dry THF was added drop-wise into the mixture. The mixture was then allowed to reflux for 3 h. After resulting grey solution was cooled to room temperature, transferred into a dry droping funnel, and added drop-wise into a dry THF solution of 3-bromothiophene (6.5 g, 40 mmol) and Ni(dppp)Cl2 (160 mg, 1.2 mmol) at 0° C. The mixture was heated to reflux overnight under nitrogen atmosphere. The mixture was then cooled and a dilute hydrochloric acid aqueous solution was added to quench excess Grignard reagent. The crude product was extracted from the mixture with hexane, washed with water, and purified by silica gel chromatography eluting with hexane. The final product was 7.2 g of colorless oil (49%). The product was characterized by 1H NMR: (CDCl3, 400 MHz, ppm) δ 7.23-7.21 (m, 1H), 6.90-6.88 (m, 2H), 2.56-2.55 (d, 2H, J=6.8 Hz), 1.61-1.59 (m, 1H), 1.25 (br, 32H), 0.90-0.87 (t, 6H).

1. temperatureheated
2. temperatureto slight reflux under nitrogen
3. temperatureto reflux for 3 h
4. customAfter resulting grey solution
5. customtransferred into a dry droping funnel
6. temperatureThe mixture was heated
7. temperatureto reflux overnight under nitrogen atmosphere
8. temperatureThe mixture was then cooled
9. customto quench excess Grignard reagent
10. extractionThe crude product was extracted from the mixture with hexane
11. washwashed with water
12. custompurified by silica gel chromatography
13. washeluting with hexane