Prepared vinyl ester

The concept for preparing vinyl esters with maleate residues has also been investigated by using hydroxyalkyl or glycidyl acrylate and methacrylate starting materials. " " For example, phthalic anhydride was treated with hydroxyethyl methacrylate and the acid esterified with glycidyl methacrylate to prepare product 3. Compound 3 was treated with MA to obtain a resin 4... 

Hydroxylethyl acrylate may be treated with MA and the reaction product subsequently treated with glycidyl ethers to prepare vinyl ester resins, with the maleate or fumarate residue within the resin chain.This concept is demonstrated with the brominated derivative of bisphenol-A diglycidyl ether starting material to prepare resin 7. Materials of this nature may be blended with other monomers and cured to give high heat distortion, corrosion-resistant and flame-resistant plastics. 

Crepeau and Marechal studied the reaction of carboxy-substituted phenol with epoxy groups (see Section 1.3.4.2). Marechal et prepared vinyl ester resins by reacting DGEBA resin... 

Catalytic vinylation has been appHed to a wide range of alcohols, phenols, thiols, carboxyUc acids, and certain amines and amides. Vinyl acetate is no longer prepared this way in the United States, although some minor vinyl esters such as stearates may still be prepared this way. However, the manufacture of vinyl-pyrrohdinone and vinyl ethers still depends on acetylene. 

Vinyl esters are prepared by the reaction of a fatty acid with either acetjfene in direct condensation or vinyl acetate by acidolysis. 

Glycidyl and Vinyl Esters. Glycidyl neodecanoate [26761-45-5] sold commercially as GLYDEXXN-10 (Exxon) or as CarduraElO (Shell), is prepared by the reaction of neodecanoic acid and epichl orohydrin under alkaline conditions, followed by purification. Physical properties of the commercially available material are given in Table 3. The material is a mobile Hquid monomer with a mild odor and is used primarily in coatings. Eor example, it is used as an intermediate for the production of a range of alkyd resins (qv) and acryHcs, and as a reactive diluent for epoxy resins (qv). 

Poly(vinyl alcohol) is thus prepared by alcoholysis of a poly(vinyl ester) and in practice poly(vinyl acetate) is used (Figure 14.5). 

Haloacetyl groups have also a synthetic potential. Thus, pesticidal (alkylthio)-vinyl esters of phosphorus acid derivatives have been prepared by the introduction and subsequent displacement of two chlorine atoms in the acetyl moiety attached to the furazan ring (Scheme 69) [73GEP(0)2144393]. 

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). 

A basic ionic liquid, l-methyl-3-butylimidazolium hydroxide ([bmIm]OH) and l-butyl-3-methyl-methylimidazolium tetrafluoroborate ([bmim]BF4), has been introduced as a catalyst and reaction medium for the Markovnikov addition of imidazoles 116 to vinyl esters 115 under mild conditions to give imidazoesters 117 <06JOC3991 06TL1555>. A series of (nitroimidazolyl)succinic esters and diacids were prepared from the Michael-type addition of the nitroimidazole to the a,P-unsaturated ester <06S3859>. 

For all practical purposes, monomeric vinyl alcohol exists only in its tautomeric form as acetaldehyde. Therefore, poly(vinyl alcohol) (PVAlc) is prepared by the hydrolysis of polymers of vinyl esters. For practical reasons, the starting material of choice is poly(vinyl acetate) (PVAc). Although hydrolysis may be carried out under acidic conditions, alkaline conditions in the presence of an alcohol are preferred. The reaction may be represented by... 

Vinyl caproate, caprylate, pelargonate, caprate, myristate, pahnitate, stearate, 10-hendecenoate (undecylenate) and oleate can be prepared in a similar manner, except that in the preparation of the pahnitate and stearate the fatty acids are added to a solution of mercuric acetate and sulfuric acid in vinyl acetate. Vinyl stearate is not redistilled, but the once-distilled product is recrystallized from acetone at 0° (3 ml. of acetone per gram of vinyl stearate). The amount of mercuric acetate employed was 2%, and the amount of 100% sulfuric acid was 0.3-0.4%, of the weight of the stearic acid. Average yields and properties of these vinyl esters are given in the table. 

The acids used for preparing the vinyl esters tal)ulated were Eastman Kodak Company [nire grade except for tlie following,... 

The procedure described is substantially that of Toussaint and MacDowell, with minor modifications. Vinyl esters of long-chain aliphatic acids have also been prepared by the reaction of acetylene with the appropriate acids, - but this reaction is not so convenient for small-scale laboratory preparationsr... 

Many such activated acyl derivatives have been developed, and the field has been reviewed [7-9]. The most commonly used irreversible acyl donors are various types of vinyl esters. During the acylation of the enzyme, vinyl alcohols are liberated, which rapidly tautomerize to non-nucleophilic carbonyl compounds (Scheme 4.5). The acyl-enzyme then reacts with the racemic nucleophile (e.g., an alcohol or amine). Many vinyl esters and isopropenyl acetate are commercially available, and others can be made from vinyl and isopropenyl acetate by Lewis acid- or palladium-catalyzed reactions with acids [10-12] or from transition metal-catalyzed additions to acetylenes [13-15]. If ethoxyacetylene is used in such reactions, R1 in the resulting acyl donor will be OEt (Scheme 4.5), and hence the end product from the acyl donor leaving group will be the innocuous ethyl acetate [16]. Other frequently used acylation agents that act as more or less irreversible acyl donors are the easily prepared 2,2,2-trifluoro- and 2,2,2-trichloro-ethyl esters [17-23]. Less frequently used are oxime esters and cyanomethyl ester [7]. S-ethyl thioesters such as the thiooctanoate has also been used, and here the ethanethiol formed is allowed to evaporate to displace the equilibrium [24, 25]. Some anhydrides can also serve as irreversible acyl donors. 

Installation began in June 1988 and was accomplished in four months. The waste treatment area was prepared and coated with a chemically resistant vinyl ester. Only after this coating had cured was the equipment brought to the site. Both Aeroscientific and TRSI supervised the installation. Plumbers and electricians logged abcut 2,000 hours over a 12 week period. 

Pratasine. The utilisation of the cyclic hydroxamic acid 230 as a late precursor of pratosine has also been described [62] (Scheme 38). The preparation of 230 was achieved in excellent yield by photocyclisation of the borate ester 231 itself obtained from hydroxamic acid 232. Aqueous hydrolysis of the cyclic borate furnished 230, which underwent a smooth Michael addition to methyl propiolate to form the O-vinyl ester 233. The latter, on thermolysis in wet dimethylsulfoxide provided, via a 3,3-sigmatropic rearrangement, pratosine (204, 17% yield) and methyl pratosine-4-carboxylate (234,35% yield). 

Core-shell rubber (CSR) particles are prepared by emulsion polymerization, and typically exhibit two or more alternating rubbery and glassy spherical layers (Lovell 1996 Chapter 8). These core-shell particles are widely used in thermoplastics, especially in acrylic materials (Lovell, 1996), and have also been used to modify thermosets, such as epoxies, cyanates, vinyl ester resins, etc. (Becu et al., 1995). 

Regioselective reactions in systems which contain multiple functional groups are an area ideally suited for biocatalysis. Linhardt and co-workers at the University of Iowa s Division of Medicinal and Natural Products Chemistry recently published the synthesis of a series of 1 -O-acyl sucrose derivatives [31], Using Chiro-CLEC -BL (the CLC of subtilisin) and vinyl esters of the acylating agent in pyridine as solvent, the authors prepared l -O-lauryl sucrose, l -O-myristyl sucrose, and l -O-stearyl sucrose in 80-90% yield (Fig. 9). Their method represents a green alternative to the tin chemistry previously used [32],... 

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... 

More recent investigations revealed that the vinyl esters of these branched acids are excellent base materials for preparing paint latices (3, 8, 9, 10, 11, 13, 14). Their use as comonomer in vinyl acetate copolymer latices imparts improved alkali resistance and weatherability to the paint films. 

Vinyl esters of trialkylacetic acid copolymerize randomly with vinyl acetate. Paint latices with a very low residual monomer content, based on vinyl acetate-W 911 copolymers, can be prepared reproducibly via a variant of the monomer emulsion addition technique, when a relatively large part of the anionic emulsifier is present in the initial reactor charge. 

The synthetic utility of this base (1) was demonstrated in the preparation of vinyl iodides in high yields from simple ketohydrazones and iodine (Table), a process that normally gives mixtures of vinyl iodides and geminal diiodides if less hindered bases are employed.6 This base has also been used in the elimination of sulfonic acids from the corresponding sulfonates, the alkylation of compounds containing active methylene groups, the conversion of hydrazones to vinyl selenides, and the preparation of esters from sterically hindered acids.4 5... 

Vinyl chloride is built into the copolymer somewhat faster than the vinyl esters. The latices described in Figure 12. were prepared with the same initial concentration of emulsifier. The difference in particle size between the homopolymer and the copolymer latices are considered to be within experimental error. 

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