1-(7-Bromoheptyl)-2,4,5-triphenylimidazole (7 g) in dry dimethylsulphoxide (15m1) was added over 20 minutes to a mixture of sodinto cyanide (0.87 g) in dimethyl-sulphoxide (25 ml ). The reaction was stirred at 40° C. for 1 hour. The cooled reaction mixture was poured into water (800 ml) and extracted with diethyl ether (4×100 ml). The extracts were combined, washed with water, dried over anhydrous magnesinm sulphate and evaporated to dryness in vacuo. Recrystallisation from dichloro-methane/hexane gave 1-(7-cyanoheptyl)-2,4,5-triphenylimidazole (3.7 g,60%) as a white solid, m.p. 93°-94°; Found: C, 82.35; H, 6.90; N, 9.96%; C29H29N3 1% CH2Cl2 requires C, 82.43; H, 6.91; N, 9.91%.
