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Experimental SectionSynthesis of 4-bromo-4'-(octyloxy) biphenyl (1) The reaction is carried out in oven-dried glassware. In a 250 ml round bottom flask 10g 4'-bromobiphenyl-4-ol and 3.86g (moles) K2CO3 were taken and dissolved in 100 ml DMF. The mixture was stirred and heated to 90 °C followed by dropwise addition of 25 ml of 1-bromooctane. The temperature of the mixture was maintained at 90° C for 5h. Then the reaction mixture was poured into 1L distilled water and transferred to a separating funnel and extracted with chloroform. The chloroform layer was washed using 5% NaOH solution and distilled water, and the organic layer was dried over anhydrous sodium sulfate. Upon evaporation white solid is obtained and is further purified by recrystallization from acetonitrile. Yield:80%. synthesis of 2,5-bis(4'-(octyloxy)-[1,1'-biphenyl]-4-yl)thiophene-3-carbonitrile: (PCN8)To a degassed mixture of 4-bromo-4'-(octyloxy) biphenyl (4.14 g, 18 mmol ), 3cyanothiophene(1g, 3.08 mmol), K2CO3 (6 mmol, 0.81g), Pd(OAc)2 (6 mol %, 0.178 mmol, 40 mg), PCy3.HBF4 (12 mol %, 0.358 mmol, 132 mg), pivalic acid (30 mol %, 0.90 mmol, 92 mg), 8 ml of dry N,N-dimethyl acetamide was added via syringe. The reaction mixture was then vigorously stirred at 110 º C for 12 h under argon. The solution was then cooled to room temperature and diluted with CH2Cl2. The aqueous phase was extracted with CH2Cl2 (3 times). The organics layer was dried over MgSO4 and evaporated under reduced pressure and then eluted with hexane /ethyl acetate (9: 1). The solid obtained was recrystallization from 1propanol. [1,2] Yield: 76%, m.p.:91.1  C.

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