Suzuki-Miyaura coupling reactions vinyl bromides

With the role of the base established, another issue in the Suzuki-Miyaura reaction was to elucidate whether the mechanism for the transmetalation step involved either one or two phosphine ligands in the Pd catalytic species. On this issue, Maseras et al. reported a thorough computational study at DFT-B3LYP level of the full catalytic cycle for the coupling of vinyl bromide and vinylboronic acid H2C=CHB(0H)2 catalyzed by both [Pd(PH3)2] and [PdfPHj)] [71]. Moreover, alternative mechanisms for the transmetalation step depending on the cis or trans... 

Coats reported a parallel synthesis of delta/mu agonists as depicted in Scheme 15.27. Both solid and solution-phase techniques were evaluated with regard to the reactivity of the vinyl bromide template but solution-phase couplings resulted in more rapid reactions. In the latter case it was found that the Suzuki-Miyaura reaction could be applied directly to the reaction mixture of the preceding reductive amination, thus ensuring a relatively rapid and easy synthetic route to a library of 192 compounds [66]. 

P-Substituted vinylboronic esters were isolated in fair to high yields from the coupling under classical Heck conditions of vinylBhg with (hetero)aryl iodides and bromides (Table 3.1, entries 1-3). A dienyl boronic ester was obtained by coupling of vinylBhg with a vinyl iodide derived from phenylgly-cine (entry 4). The preparation of a styryl boronic ester with a sulfonamide moiety is described in a patent (entry 5) this product was later used in a Suzuki-Miyaura reaction. ... 

The Suzuki-Miyaura reaction is perhaps one of the most well-known coupling protocols developed to date. A seareh of the literature reveals over 15000 citations to work employing this eoupling protocol that was first developed in 1979 and for whieh Akira Suzuki shared the Nobel Prize in Chemistry in 2010. The two seminal papers in 1979 co-authored by Suzuki and Miyaura deseribe the eross-eoupling of vinyl boronic acids with vinyl bromides (Scheme 13.1) or aryl halides (Scheme 13.2), employing 1 mol.% tetrakis(triphenylphosphene)palladium and a base such as sodium ethoxide. The stereoselectivity of the reactions was excellent with >99% retention of double bond geometry. The evolution of the various Suzuki coupling partners is shown in Scheme 13.3. 

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