Allyl alcohols were converted to allyl boronic acids and subsequently to trifluoro(allyl)borates with tetrahydroxy diboron using palladium pincer-complex catalysis. These reactions are regio- and stereoselective proceeding with high isolated yields. Competitive boronation experiments indicate that under the applied reaction conditions the allylic displacement of a hydroxy group is faster than the displacement of an acetate leaving group. It is assumed that the hydroxy group of the allyl alcohol is converted to a diboronic acid ester functionality, which can easily be substituted.

Palladium-catalyzed boronation of vinyl cyclopropane, vinyl aziridine, and allyl acetate substrates could be accomplished using tetrahydroxydiboron reagent in the presence of SeCSe pincer complex catalyst 1a. These reactions result in allyl boronic acids, which were converted to synthetically useful trifluoro(allyl)borates or allyl boronates. The catalytic transformations proceed under mild and neutral conditions, and therefore many functionalities Br, COOEt, ArSO2(NH), OAc, and SiRMe2 are tolerated. The selectivity of the presented processes is very high, affording the linear products incorporating a trans double bond.

Palladium-catalyzed coupling reactions of functionalized allylboronic acids with iodobenzenes were achieved under standard Suzuki-Miyaura coupling conditions. The coupling reactions afforded selectively the branched allylic products in high to excellent yields. In contrast to palladium-catalyzed nucleophilic substitution reactions proceeding via (eta3-allyl)palladium intermediates, this process does not require directing groups in the allyl moiety to achieve substitution at the congested allylic terminus. The regioselectivity of the process was largely unaffected by the substituent effects of the iodobenzenes and the allylic substrates.

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