Heck reaction polymerization

Microwave irradiation was applied to the synthesis of base-stable ionic liquids [210]. For example, N-alkyl-AA -dimethylethanolamine salts were prepared and used in several reactions, for instance Mizoroki-Heck reaction, polymerization or condensation reactions, with good yield (95%). 

Heck Reaction Polymerizations. The Heck reaction is readily applicable to the synthesis of poly(arylenevinylene)s and poly(heteroarylvinylene)s. Poly(l,4-phenylenevinylene)s have been prepared with both AA/BB-monomer pairs and AB-monomers. The AA/BB-monomer pairs are typically dihalogenated arenes and ethylene (797) or divinylarenes (798). Bromostj ene (equation 61) is an example of an AB-monomer (799). The molecular weight of the polymer obtained by the polymerization of 4-bromostyrene (equation 61) was limited by its poor solubility (799). 

Polyethylene glycol) (PEG) was used as a soluble polymeric support in the efficient preparation of the 2-benzazepine 58 via a phosphine-free palladium-catalysed Heck reaction from 57 <06T10456>. 

Benzamido-cinnamic acid, 20, 38, 353 Benzofuran polymerization, 181 Benzoin condensation, 326 Benzomorphans, 37 Benzycinchoninium bromide, 334 Benzycinchoninium chloride, 334, 338 Bifiinctional catalysts, 328 Bifiinctional ketones, enantioselectivity, 66 BINAP allylation, 194 allylic alcohols, 46 axial chirality, 18 complex catalysts, 47 cyclic substrates, 115, 117 double hydrogenation, 72 Heck reaction, 191 hydrogen incorporation, 51 hydrogen shift, 100 hydrogenation, 18, 28, 57, 309 hydrosilylation, 126 inclusion complexes, oxides, 97 ligands, 19, 105 molecular structure, 50, 115 mono- and bis-complexes, 106 NMR spectra, 105 olefin isomerization, 96... 

Benzofurans and dihydrobenzofurans have been prepared on polymeric supports by the palladium-mediated reaction of 2-iodophenols with dienes or alkynes (Entries 1 and 2, Table 15.9). This reaction is closely related to the synthesis of indoles from 2-iodoanilines, and probably proceeds via an intermediate palladacycle (Figure 15.3). Benzofuran and isobenzofuran derivatives have also been prepared on cross-linked polystyrene by intramolecular addition of aryl radicals to C=C double bonds and by intramolecular Heck reaction. 

Mizoroki-Heck reaction, for cross-coupling polymerization,... 

Schwarz et al. [326] synthesised a functionalised bis-imidazolium salt with hydroxy end groups on the wingtips [327,328] and used it in the formation of chelating cw-bis-carbene complexes of palladium(ll) applied as catalysts in the Heck reaction. The functional groups were needed to immobilise the catalyst by attachment to a polymeric support [329] (see Figure 3.104). 

Richard F. Heck (bom 1931) was a student of Saul Winstein (UCLA) and Vladimir Prelog (ETH Zurich). He started mechanistic work on homogeneous catalysis in 1956 when he entered Hercules Inc. (Wilmington, Del., USA) as a research chemist. He pioneered the elucidation of reaction mechanisms of organometallic processes, e. g., hydro-formylation and Ziegler-Natta polymerization, and published a number of key papers about the chemical and mechanistic backgrounds of these reactions. He was a chemistry professor at the University of Delaware from 1971 until his retirement in 1989. For the Heck reaction the reader is referred to Section 3.1.6. 

Chapters 8 and 11 emphasized that there are relatively few instances of insertion of a C=C bond into an M-C bond, with Z-N polymerization serving as the most significant example. Perhaps the migratory C=C insertion most useful to synthesis chemists is the Heck reaction, which is also known as Heck olefination.89... 

---