A mixture of 1-bromo-4-octyloxybenzene (compound 22) (10.0 g, 0.0351 mol), 2-(tributylstannyl)thiophene (14.4 g, 0.0386 mol) and tetrakis(triphenylphosphine)-palladium (0) (1.22 g, 1.05×10−3 mol) in DMF (200 cm3) was heated at 90° C. for 24 h. The mixture was allowed to cool to RT and the solution was treated with a saturated potassium fluoride solution (100 cm3) to destroy the tin side products. Hexane (2×200 cm3) was added and the combined organic layers were washed with brine (2×200 cm3), water (200 cm3), dried (MgSO4), filtered and concentrated under reduced pressure. Catalyst residues were removed by passing the crude product though a short column containing silica gel [DCM: hexane, 50%: 50%]. The product was recrystallised from ethanol, filtered and washed with cold ethanol (2×30 cm3) to yield a light blue crystalline solid (5.00 g, 49.5%). Melting point/° C.: 68–70.
