Potassium-tert-butoxide (2.46 g) was added to a stirred, ice-cooled suspension of (4-butoxybenzyl)-triphenylphosphonium bromide (10.1 g) in dry tetrahydrofuran (300 ml) under an atmosphere of argon. The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was cooled to -10° C. and a solution of 3-formylquinuclidine (750 mg) in dry tetrahydrofuran (20 ml) was added dropwise over 15 minutes. The reaction mixture was stirred at room temperature overnight and water (1.0 ml) was then added. The tetrahydrofuran was evaporated and the residue was triturated several times with ether and filtered. The ether extracts were combined and evaporated to give an oil which was purified by flash column chromatography, using 10% methanol in dichloromethane containing 1% 0.880 ammonia as eluent, to give Z-3-[2-(4-butoxyphenyl)vinyl]-quinuclidine (Rf=0.3). This was dissolved in ether and an excess of a solution of hydrogen chloride in ether added to give a solid which was collected by filtration. There was thus obtained Z-3-[2-(4-butoxyphenyl)vinyl]quinuclidine hydrogen chloride as a colourless solid, m.p. 146°-149° C. (220 mg); microanalysis, found: C, 68.2; H, 8.4; N, 4.2%; C19H27NO.HCl.0.75H2O requires: C, 68.06; H, 8.8; N, 4.18%; NMR (DMSO-d6): 0.9-0.97(3H, t), 1.35-1.49(2H, m), 1.66-2.16(8H, m), 2.82-2.95(1H, m), 3.08-3.3(4H, m), 3.41-3.58(1H, t), 3.9-4.03(2H, t), 5.65-5.78(1H, d of d), 6.43-6.53(1H, d, J=11 Hertz), 6.9-7.0(2H, d) and 7.16-7.26(2H, d); m/Z 286 (M+H).
