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Polyenyl-1-boronic acids, with hindered pinacol esters, are difficult to transform into the corresponding Z - or E -iodides under literature reaction conditions. However, reaction of trans -polyenyl-1-boronate pinacol esters with sodium methoxide, followed by monochloroiodide provides the corresponding E -iodides, while reaction with monochloroiodide, followed by sodium methoxide provides the corresponding Z -iodides.

Vinylboronate 1 , protected as its pinacol ester, can be cross-coupled with aryl halides in the presence of palladium(0) to give the styrylboronate 2 as the major or exclusive product under optimized reaction conditions. The styrylboronate Heck products 2 are obtained with higher yields when aryl iodides rather than aryl bromides are used. Heteroaromatic halides are only reactive when silver(I) salts are added to the reaction mixture.

Palladium(O) catalysed cross-coupling of a vinylboronate 1 , protected as its' pinacol ester, with aryl halides provides a mixture of the styryl boronates 2 and the styrenes 3 depending upon the reaction conditions.

Reaction of alkynes with ICI and an iodide source results in the stereoselective formation of diiodoalkenes in moderate to high yield. At r.t., the reaction is stereospecific, resulting in the formation of E-diiodoalkenes, however lowering the temperature and using a more soluble iodide source results in a stereoselective formation of the Z-diiodoalkenes.

E- and Z-1-alkenyl iodides react with vinylboronate pinacol ester 1 under palladium(0) catalysed, Heck conditions to provide polyenylboronates in moderate yields after purification. The addition of either silver(I) or thallium(I) salts to the reaction mixture is essential. Alkenyl bromides are unreactive under identical reaction conditions.