Tributyltin acrylate

About 50 g of pure tributyltin acrylate (TBTA) was dissolved in 1 liter hexane. Evaporation of 20 ml of this solution yielded a solid residue, weighing 0.9796 g. 

Controlled release epoxy formulations in which tin is chemically anchored as tributyltin carboxylate to the polymer chain are discussed. NMR evidence is presented to establish that rapid exchange exists in tributyltin carboxylates. Consequently, even the interfacial reaction between tributyltin carboxylates and chloride is very fast equilibrium constants are reported for the reaction between tributyltin acrylate in hexane and sodium chloride in water. IR spectra, gas chromatographic retention time, chloride assay, and the complex intensity pattern of the molecular ion peaks in the mass spectrum show that the product of the reaction is tributyltin chloride, suggesting that it is the chemical species responsible for antifouling activity in marine environment. 

Because manufacturers are unwilling to generate data to substantiate the acceptability of continued use, the other tin compounds of the case have become obsolete, including bis (tributyltin) adxpate[7437-35-6]y bis(tributyltin) sulfosalicylate/44/5M 2-/]y tributyltin acetate [56-36-0], tributyltin acrylate[13331-52-7], tributyltin chloride[1461 -22-9]y tributyltin linoleate/24124-25-2], tributyltin monopropylene glycol maleate[53466-85-6]y and tributyltin neodecanoate[28801 -69-6]. Because of the substantial number of tin compounds, this is not a typical example, but it does illustrate the point that there has been a large decline in the availability of niche products. 

A copolymer of tributyltin acrylate and methyl methacrylate in butyl acetate was synthesised, and the effectiveness of this additive in protecting paints and varnishes against moulds and fungi was studied. 4 refs. Articles from this journal can be requested for translation by subscribers to the Rapra produced Intematiorral Polymer Science and Technology. 

Compositionally uniform copolymers of tributyltin methacrylate (TBTM) and methyl methacrylate (MMA) are produced in a free running batch process by virtue of the monomer reactivity ratios for this combination of monomers (r (TBTM) = 0.96, r (MMA) = 1.0 at 80°C). Compositional ly homogeneous terpolymers were synthesised by keeping constant the instantaneous ratio of the three monomers in the reactor through the addition of the more reactive monomer (or monomers) at an appropriate rate. This procedure has been used by Guyot et al 6 in the preparation of butadiene-acrylonitrile emulsion copolymers and by Johnson et al (7) in the solution copolymerisation of styrene with methyl acrylate. 

Glass transition data for copolymers and terpolymers of controlled and uncontrolled composition are shown in Figures 6 and 7. The Tg s calculated using the equations 7 and 8 of Fox (12) and Woods (13) have been used with the following hompolymer Tg s methyl methacrylate, 108°C tributyltin methacrylate, 0°C 2-ethylhexyl acrylate, -50"C (14-16) are also shown. 

The presence of the propionamide fragment in the stmcture of the anti-inflammatory agent broperamole (125-1) is reminiscent of the heterocycle-based NSAID propionic acids. The activity of this agent may trace back to the acid that would result on hydrolysis of the amide. Tetrazoles are virtually always prepared by reaction of a nitrile with hydrazoic acid or, more commonly, sodium azide in the presence of acid in a reaction very analogous to a 1,3-dipolar cycloaddition. A more recent (and safer) version of the reaction noted later (see losartan, 77-4) uses tributyltin azide. In the case at hand, reaction of the anion of mefa-bromobenzonitrile (125-1) with sodium azide and an acid affords the tetrazole (125-2). Condensation of the anion from that intermediate with ethyl acrylate leads to the product from Michael addition saponiflcation gives the corresponding carboxylic acid (125-3). This is then converted to the acid chloride reaction with piperidine affords broperamole (125-4) [136]. 

As can be seen, the isolation of l-halobicyclo[l.l.l]pentanes offered an opportunity for further molecular manipulation. To illustrate this, the adduct generated from 3-iodo-4,5-dihy-drofuran-2(3//)-one and [1.1.IJpropellane was reacted with tributyltin hydride in the presence of the radical trapping agent methyl acrylate to afford the 1,3-disubstituted biey-clo[l.l.l]pentane 27 in a total yield of 39%.43... 

Monomers like iron (III) methacrylate [CH2=C(CH3)-COO] 3Fe and tributyltin methacrylate have been synthesized [3]. They undergo free radical polymeriz-ation/copolymerization with other acrylates such as cyclohexyl, 2-ethoxyethyl, 2-hydroxyethyl and 2-hydroxypropyl. Synthesis of a metailo-macrocyclic acrylic monomer is illustrated by the reaction between a metallophthalocyanine tetracarbonyl chloride (1) and 2-hydroxyethyl methacrylate (2-HEMA) [4]... 

The simple addition reaction in Scheme 19 illustrates how the notation is used. Ester (1) can be dissected into synthons (2), (3) and (4). Synthons for radical precursors (pro-radicals) possess radical sites ( ) A reagent that is an appropriate radical precursor for the cyclohexyl radical, such as cyclohexyl iodide, is the actual equivalent of synthon (2). By nature, alkene acceptors have one site that reacts with a radical ( ) and one adjacent radical site ( ) that is created upon addition of a radical. Ethyl acrylate is a reagent that is equivalent to synthon (3). Atom or group donors are represented as sites that react with radicals ( ) Tributyltin hydride is a reagent equivalent of (4). In practice, such analysis will usually focus on carbon-carbon bond forming reactions and the atom transfer step may be omitted in the notation for simplicity. 

Adaptation of these cyclization reactions allows for the introduction of new C-C-bonded substituents so that, for example, when the bromoethyl glycoside 216 is activated with radicals generated with allyltributyltin (in place of the tributyltin hydride), the main product is the 3-C-allyl compound 218. Otherwise, branching can be introduced by carrying out the radical-promoted reactions in the presence of radical-trapping species such as methyl acrylate.218 With appropriate compounds, the initial organic radicals formed during intramolecular cyclization can be trapped by... 

Other trialkyltin-containing monomers such as 3-tributyltinstyrene (84), tributyltin methacrylate (85) and 4-[bis(trimethylstannyl)methyl]styrene (86) were also reported to homo- and copolymerise with styrene under radical conditions175-177. In addition, 3-tributyltinstyrene (84) was copolymerised under radical conditions with ethyl acrylate, methyl methacrylate, vinyl acetate and acrylonitrile175. A functional methacrylate-based polymer was prepared by the copolymerization of the triorganotin methacrylate monomer 87 with styrene and divinylbenzene178,179. 

As shown in Equation (16), reaction of an allyl o-iodoaryl ether with tributyltin hydride in the presence of the activated alkene ethyl acrylate gives a mixture of 2-substituted dihydrofuro[3,2-AJquinolines (41) <89H(28)373>. 

Caddick [19] has reported the use of a novel polymer-supported tetra-fluorophenol-Unked acrylate as an activated acceptor for intermolecular radical reactions. Treatment of immobiUzed acrylate 132 with a variety of alkyl iodides in the presence of tributyltin hydride and AIBN gave the corresponding esters 133 (Scheme 29). NucleophiUc cleavage using amines gave amides 134 in good overall yield whilst regenerating phenol resin 131. 

The triorganotin species have been used as industrial biocides for over 30 years [117, 118]. Examples are triphenyltin hydroxide (structure 5) for fungal diseases on celery, rice, sugar beets, and coffee tricyclohexylstannyl-1,2,4-triazole (structure 6) as an acaricide for apple, pear, and citrus fruit trees bistributyltin oxide (structure 7) as a wood preservative and tributyltin-methylacrylate monomers (structure 8) polymerized with other acrylates to yield a marine antifoulant polymer that prevents the build of up barnacles, algae, and other marine animals on ships. 

The coupling of homoallylic iodide with a,) -unsaturated esters and nitriles is valuable in obtaining simple addition products with ethyl acrylate and acrylonitrile. While tributyltin hydride gives the sequential cyclization products 46 and 48 as the major products [17], the BER-Ni2B system yields the simple addition compounds 45... 

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