Tributylvinyltin (0.28 ml) was added to a deoxygenated suspension of (R)-N-[2-bromo-4-(4-mesylphenylsulphonyl)phenyl]-2-hydroxy-2-methyl-3,3,3-trifluoropropanamide (Example 140) (0.50 g) and tris(dibenzylideneacetone)dipalladium(O) (0.05 g) in anhydrous toluene (10 ml). The mixture was heated under reflux with stirring. After 14 hours a further portion of tris(dibenzylideneacetone)dipalladium(0) (0.05 g) and tributylvinyltin (0.28 ml) was added and heating was continued for a further 7 hours. The reaction mixture was allowed to cool and volatile materials were removed by evaporation. The residue was purified on a silica gel Mega Bond Elut column eluting with 5-50% ethyl acetate/hexane to give the title compound (0.146 g) as a solid. NMR (CDCl3) 1.74 (s, 3H), 3.06 (s, 3H), 5.65-5.82 (dd, 2H), 6.67-6.77 (dd, 1H), 7.86-7.89 (dd, 1H), 7.95 (s, 1H), 8.06-8.16 (m, 4H), 8.35 (d, 1H), 8.79 (s, 1H); MS (ESP−): 477.
