Functionalisation of homopropargyl boronic esters via hydrozirconation followed by Pd-catalysed cross coupling reaction

Hydrozirconation of homopropargyl boronic esters accessible via Matteson homologation allows their selective functionalisation while retaining the boronic ester functionality. In this study, reactions of vinyl zirconium reagents derived from boronic esters in Negishi coupling, in particular with benzyl halides and aryl iodides, are presented. Different synthesis routes for the stereoselective assembly of (E)- and (Z)-alkenes are discussed.