Various N-vinyl- and N-allyl-amides of 2-iodobenzoic acid undergo catalytic cyclisation in the presence of tetraethylammonium chloride and a palladium acetate-based catalyst system to generate a range of synthetically useful structural features including tetrasubstitutedcarboncentres, and spiro- and bridged-ringcompounds, and in which 5-exo-trig cyclisations are kinetically favoured.
A catalyst system comprising 10 mol % (Pd(OAc) and 20 mol % PPh3 effects the cyclisation of aryl halides onto proximate alkenes via 5-, 6-, and 7-exo-trig, and 7-endo-trig processes giving a variety of bridged-ring carbo- and hetero-cycles in excellent yield. Double bond isomerisation in the product is rarley encountered and may be suppressed by the addition of Tl(1) salts. One example of diastereospecific