7-Bromoheptyl prop-2-ynyl ether (55.1 g) in THF (250 ml) was added dropwise over ca 8 h to a stirred mixture of 3-bromobenzenesulfonamide (43.5 g), PdCl2(PPh3)2 (6.48 g), PPh3 (1.45 g), CuI (1.4 g) and Et3N (52 ml) in THF (250 ml) at 55±5° C. under nitrogen then the mixture heated for a further ca 15 hrs. The reaction was cooled, filtered through Celite and the solids washed with THF. The solution was concentrated and the product purified by chromatography on flash silica gel (600 g) eluting with petroleum ether:ethyl acetate (ratios ranging successively from 19:1 to 7:3) to give the title compound (33 g)—LC RT=5.85 min.
