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Vinyl esters ketones

Tsuda156 reported the preparation of poly(vinyl 2-furylacrylate) by the reaction of 2-furylacrylyl chloride with poly(vinylalcohol) in NaOH-water-methyl ethyl ketone. Up to 80% of the hydroxyl groups were esterified. The interest of this technique is obvious here, considering that the vinyl ester of 2-furylacrylic acid does not polymerize119 A similar procedure was employed by Gandini and Rieumont26,1 9 for the synthesis of poly(vinyl 2-furoate) another product unobtainable via a standard polymerization process (see Section 1II-B-3). [Pg.85]

In the presence of metal catalysts such as rhodium compounds, aldehydes can add directly to alkenes to form ketones. The reaction of co-alkenyl aldehydes with rhodium catalyst leads to cyclic ketones, with high enantioselectivity if chiral ligands are employed. Aldehydes also add to vinyl esters in the presence of hyponitrites and thioglycolates. ° ... [Pg.1038]

The most characteristic and useful reaction is the dimerization with incorporation of certain nucleophiles. It is well-known that simple olefins coordinated by Pd2+ compounds undergo nucleophilic substitutions [Eq. (9)] or addition reactions [Eq. (10)] (16, 17). Water, alcohols, and carboxylic acids are typical nucleophiles which attack olefins to form aldehydes, ketones, vinyl ethers, and vinyl esters. [Pg.145]

The a-arylation of carbonyl compounds (sometimes in enantioselective version) such as ketones,107-115 amides,114 115 lactones,116 azlactones,117 malonates,118 piperidinones,119,120 cyanoesters,121,122 nitriles,125,124 sul-fones, trimethylsilyl enolates, nitroalkanes, esters, amino acids, or acids has been reported using palladium catalysis. The asymmetric vinylation of ketone enolates has been developed with palladium complexes bearing electron-rich chiral monodentate ligands.155... [Pg.314]

Methylenesulphones are more acidic than the simple esters, ketones and cyano compounds and are more reactive with haloalkanes [e.g. 48-57] to yield precursors for the synthesis of aldehydes [53], ketones [53], esters [54] and 1,4-diketones [55] (Scheme 6.4). The early extractive alkylation methods have been superseded by solidtliquid phase-transfer catalytic methods [e.g. 58] and, combined with microwave irradiation, the reaction times are reduced dramatically [59]. The reactions appear to be somewhat sensitive to steric hindrance, as the methylenesulphones tend to be unreactive towards secondary haloalkanes and it has been reported that iodomethylsulphones cannot be dialkylated [49], although mono- and di-chloromethylsulphones are alkylated with no difficulty [48, 60] and methylenesulphones react with dihaloalkanes to yield cycloalkyl sulphones (Table 6.5 and 6.6). When the ratio of dihaloalkane to methylene sulphone is greater than 0.5 1, open chain systems are produced [48, 49]. Vinyl sulphones are obtained from the base-catalysed elimination of the halogen acid from the products of the alkylation of halomethylenesulphones [48]. [Pg.240]

Another example showing the utility of 1 is the asymmetric hydrogenation of vinyl esters which usually are used as acyl donors in enzymatic resolution. In this transformation, vinyl esters are converted to ketones which then undergo asymmetric reductive acylation to give chiral esters as described in Scheme 1.13. The overall reaction thus corresponds to the asymmetric hydrogenation of vinyl ester to the corresponding alkyl esters. [Pg.10]

Catalyst Reaction time min Conv. 2 % 0- ketone Product selectivity / % p- Vinyl Side ketone 3 ester products ... [Pg.348]

As expected, the para-acylated ketone 3 is the major reaction product, with only minor yields of the ortho-acylated product formed. Reaction is very rapid and complete conversions are obtained. Catalyst TOP numbers are >19000h under these conditions. Enolisation and further reaction with the anhydride results in formation of the vinyl ester. Minor amounts of diacile and side products are formed. Similar performances are observed with both supported and nonsupported ST A (at equivalent ST A loading in reactor). Use of nonsupported ST A resulted in agglomeration and deposition of the material onto the reactor wall, whereas the silica supported material could be readily removed by filtration. [Pg.349]

Temperature rc Conv. 2 /% p-Ketone 3 Product selectivity /% o-Ketone Vinyl ester Side prods... [Pg.350]

Matrix materials for commercial composites are mainly liquid thermosetting resins such as polyesters, vinyl esters, epoxy resins, and bismaleimide resins. Thermoplastic composites are made from polyamides, polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polysulfone, polyetherim-ide (PEI), and polyamide-imide (PAI). [Pg.207]

Unsaturated Carbonyl Compounds 0-95 Vinylation of ketones or carboxylic esters... [Pg.1299]

Two resins were used to do the first study on laminate construction. The first was a brominated epoxy vinyl ester resin with antimony pentoxide and the second was a brominated unsaturated polyester resin. They were both promoted to cure at room temperature with methyl ethyl ketone peroxide catalyst. The panels were then postcured at 250°F (121°C) for 8 h. Panels were prepared that varied in glass content from 25% to 70% and panel thickness varying from 0.05 in. to 0.25 in. and were tested at the same testing facility. A summary of the FSI test data for the first set of panels tested are shown in Figures 23.1 and 23.2. This graph in Figure 23.1 plots the FSI value versus the panel thickness. This data would indicate that the thickness of the test panel has no effect on the measured... [Pg.710]

The solubility of the polymer in various media is dependent on the nature of its vinyl groups. Polyvinylmethyl ether dissolves in aromatic hydrocarbons, esters, ketones, alcohols, and cold water. However, polyvinylbutylether is soluble in aliphatic hydrocarbons but not in water, methanol and ethanol. Polyvinyloctadecyl ether possesses a wax-like consistency. The polymers can be mixed with one another as well as with many natural resins and plastics. [Pg.36]

Next, the scope of this C-glycosylation reaction was investigated. The NeuSAc chloride was found to serve as a donor in samarium mediated C-glycosylation, unfortunately, purification of C-glycoside from excess chloride donor is often problematic, making the NeuSAc phenyl sulfone the donor of choice. A variety of acceptors were also evaluated including alkenes, epoxides, vinyl esters, aldehydes and ketones. Only the aldehydes and ketones afforded the desired C-glycoside products. [Pg.60]

In the course of acyloxycarbocation investigations112 it has been noted that the reactions of both aldehydes and ketones follow an unusual course or are strongly accelerated if either acylium ions RCO+ are present in the reaction mixtures or conditions to generate them in situ arise. These observations are explained by a transformation of carbonyl compounds into the highly reactive acyloxycarbocations 163 which easily react with weak nucleophiles such as vinyl ethers, vinyl esters, etc. Hence the electrophilic catalysis by acyl cations in carbonyl reactions takes place regardless of the origin of the latter. This catalysis was used in the reaction of ketones with nitriles. [Pg.1468]

Polyethylene terephthalate (PET). At temperatnres above 300°C PET pyrolysis proceeds via a random-chain scission of the ester links to yield a mixture of terephthalic acid monomer and vinyl ester oligomers [47], The presence in the monomer of oxygen and a benzene ring imphes that the decomposition prodncts contain aromatic and oxygenated carbon componnds, like CO2, ketones and aldehydes [27],... [Pg.464]


See other pages where Vinyl esters ketones is mentioned: [Pg.316]    [Pg.316]    [Pg.136]    [Pg.453]    [Pg.321]    [Pg.461]    [Pg.1691]    [Pg.475]    [Pg.347]    [Pg.371]    [Pg.387]    [Pg.333]    [Pg.37]    [Pg.38]    [Pg.75]    [Pg.106]    [Pg.110]    [Pg.294]    [Pg.321]    [Pg.67]    [Pg.341]    [Pg.102]    [Pg.302]    [Pg.288]    [Pg.343]    [Pg.461]    [Pg.294]    [Pg.302]    [Pg.315]    [Pg.222]    [Pg.59]    [Pg.89]    [Pg.248]   


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Acetoxy-ketones => vinyl esters

Esters vinyl

Ketone esters

Ketone ketonic ester

Vinyl ketones

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