The reaction of iodoesters 1a-c with electrophilic olefins 2a-d and in situ generated tributyltin hydride (from a substoichiometric amount of tributyltin chloride and an excess of sodium borohydride) in the presence of a catalytic amount of AIBN in ethanol at 0 to 20° C yields the expected coupling products 3aa-3cd. Products 4 resulting from an iodine/hydrogen exchange are also obtained as by-products in variable amounts. The stereochemistry of ...