Acrylic and Allylic Compounds

The activity of transition metal allyl compounds for the polymerization of vinyl monomers has been studied by Ballard, Janes, and Medinger (10) and their results are summarized in Table II. Monomers that polymerize readily with anionic initiators, such as sodium or lithium alkyls, polymerize vigorously with allyl compounds typical of these are acrylonitrile, methyl methacrylate, and the diene isoprene. Vinyl acetate, vinyl chloride, ethyl acrylate, and allylic monomers do not respond to these initiators under the conditions given in Table II. 

The dimerization of functionalized olefins by transition metal catalysts is a well studied reaction. A first review was given by Lefebvre and Chauvin in 1970 [40]. In 1974 Hidai and Misono described in detail the dimerization of acrylic compounds [41]. These starting olefins have found considerable attention from the industrial point of view, because they can be produced at high quantities and at low costs by the petrochemical industry. For instance, acrylonitrile, acrylates and allyl esters are favorable starting molecules. 

Reactions of the hydrido(hydroxo) complex 2 with several substrates were examined (Scheme 6-14) [6]. The reactions are fairly complicated and several different types of reachons are observed depending on the substrate. Methyl acrylate and small Lewis bases such as CO, P(OMe)3, BuNC coordinate to the five-coordinated complex 2 affording the corresponding six-coordinate complexes. In reactions with the unsaturated bonds in dimethylacetylenedicarboxylate, carbon dioxide, phenylisocyanate indications for the addition across the O-H bond but not across the Os-OH bond were obtained. In reactions with olefins such as methyl vinyl ketone or allyl alcohol, elimination of a water molecule was observed to afford a hydrido metalla-cyclic compound or a hydrido (ethyl) complex. No OH insertion product was obtained. 

In 1991, Li and Chan reported the use of indium to mediate Barbier-Grignard-type reactions in water (Eq. 8.49).108 When the allylation was mediated by indium in water, the reaction went smoothly at room temperature without any promoter, whereas the use of zinc and tin usually requires acid catalysis, heat, or sonication. The mildness of the reaction conditions makes it possible to use the indium method to allylate a methyl ketone in the presence of an acid-sensitive acetal functional group (Eq. 8.50). Furthermore, the coupling of ethyl 2-(bromomethyl)acrylate with carbonyl compounds proceeds equally well under the same reaction conditions, giving ready access to various hydroxyl acids including, for example, sialic acids. 

Acrolein is a metabolite of allyl alcohol and cyclophosphamide, and these compounds should be considered in acrolein metabolism schemes (Beauchamp et al. 1985 Cohen et al. 1992). Allyl alcohol in the presence of NADPH and liver or lung microsomes degrades to acrolein, acrylic acid, and glycidol (Figure 10.1). 

Recently, two new axially chiral compounds 44 and 45 have been prepared [44, A-acryl-A-allyl-o-t-butylanilide 45, A-(o-t-butylphenyl)-2-methyl-maleimide]. This represents the first instance of using nonbiaryl axially chiral ligands in asymmetric Dield-Alder reactions. In the presence of iodine, high endo-facial and diastereofacial selectivities have been obtained in 44/45-medi-ated reactions.10... 

Maleate Surfmers. Surfmers with allylic, acrylic and vinylic moieties tend to homopoly-merize and produce water-soluble polyelectrolytes if used above their CMC. This has shifted researchers attention to maleic derivatives that do not homopolymerize at normal temperatures because their ceiling temperature is too low. Tauer and co-workers have pioneered the synthetic work [4,15] which led originally to compounds like those given in Figure 6.49. An example of maleic-derived Surfmer used in emulsion polymerization lattices is reported in [16] and the advantages provided in commercial paint formulations are discussed later. 

Alkoxy-l-boronobutadiene reacted with maleimides, acrylates, and acrylamides to provide cyclic allyl boronates which undergo allylboration with aldehydes (Equation (148)).409 Analogous syntheses of cyclic allylboron compounds via [2+4]-cycloaddition is discussed in Section 9.05.2.2.1. 

Cahiez, Knochel, and co-workers have developed a mixed catalytic system consisting of MnBr2/GuGl and diethyl-zinc in iV,A -dimethylpropyleneurea (DMPU), which can be used for the stereocontrolled formation of tetrahydro-furan organozinc compounds from readily available unsaturated bromoacetals. The organozinc compounds are readily transmetalated with GuGN-2LiGl, and upon treatment with ethyl (o -bromomethyl)acrylate or ethyl propiolate homoallyl- and allyl-substituted bicyclic tetrahydrofurans are obtained in 71% and 63% yield (Scheme 70). 

Acrolein, acrylamide, hydroxy alkyl acrylates, and other functional derivatives can be more hazardous from a health standpoint than acrylic acid and its simple alkyl esters. Furthermore, some derivatives, such as the allyl 2-cliloroacrylates, are powerflil vesicants and can cause serious eye injuries. Thus, although the hazards of acrylic acid and the normal alkyl acrylates are moderate and they can be handled safely with ordinary care to industrial hygiene, this should not be assumed to be the case for compounds with chemically different functional groups (see Industrial hygiene Plant safety Toxicology). 

Copolymerisation of N-vinylpyrrolidone or acrylic acid with other functional monomers such as allylic compounds and vinyl ethers results in the formation of polymers widi excellent solubility properties and metal-ion binding capacities ... 

The third type of composition is exemplified acrylate- and methacrylate-ester derivatives of epoxy resins combined with a photoinitiator 1. Epo prepolymers (e. g., glycidyl methacrylate-allyl glycidyl ether copolymers or Ciba ECN 1299) combined with a photosensitive aryldiazonium compound (e.g.,... 

The third type of composition is exemplified by acrylate- and methacrylate-ester derivatives of epoxy resins combined with a photoinitiator 1. Epoxy prepolymers (e. g., glycidyl methacrylate-allyl glycidyl ether copolymers or Ciba ECN 1299) combined with a photosensitive aryldiazonium compound (e.g., -nitrobenzenediazonium hexaflourophosphate) (38,39) 2. Epoxy prepolymers (e.g., a diglycidyl ether of disphenol A-(3,4-epoxycyclohexyl)-methyl-3,4-epoxycyclohex-anecarboxylate-alkyl glycidyl ether mixture) combined with a photosensitive aryldiazonium compound (e.g., -chlorobenzenediazonium hexaflourophosphate) and l-methyl-2-pyrrolidone gelation inhibitor (40) ... 

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