Patent GB-837220-A (GB)
Title: Methylenephenylvaleric acids and esters and preparation thereof
Filed: 1957-01-08
Abstract: The invention comprises compounds of formula <FORM:0837220/IV (b)/1> wherein R1 is hydrogen or an alkyl group having up to four carbon atoms and R is hydrogen or an alkyl or cycloalkyl group of not over eighteen carbon atoms.  They are prepared by reacting, at a temperature in the range of about 200-450 DEG  C. and a pressure of about 400-4000 p.s.i.g., a -methylstyrene and a compound of formula <FORM:0837220/IV (b)/2> wherein R and R1 are as defined above.  A solvent such as benzene or toluene may be used in the reaction mixture and is preferred when R is hydrogen to minimize polymerization.  The reaction is preferably continuous with rapid treating and cooling of the reactants.  The reaction is also preferably conducted in the absence of air and a polymerization inhibitor such as hydroquinone or its monomethyl ether, di-b -naphthol, a dihalonaphthol or para-phenylenediamine may be added. The reactants are used in equimolar amounts or with an excess of a -methylstyrene.  If an ester reactant wherein R = methyl is used, the product obtained may be transesterified, in the presence of a catalyst and if desired a solvent such as toluene or xylene, with an alcohol ROH wherein R is an alkyl group having 2-18 carbon atoms. Specified catalysts are sulphuric acid, butanesulphonic acid, p-toluenesulphonic acid, sulphonated polystyrene or phenol-formaldehyde resins and sodium methoxide. The compounds and derivatives thereof may be used as insecticides or fungicides (see Group VI) and as plasticizers or in resin compositions (see Group IV (a))  The derivatives mentioned are the copper salts, the products obtained by chlorinating the double bond of the methylene group and the products obtained by reaction with formaldehyde whereby the methylene group is replaced by an hydroxyethyl group.  In examples: (1) a mixture of methyl methacrylate and a -methyl-styrene is pumped through a stainless-steel reaction coil heated to 310-325 DEG  C. and under a pressure of 1000 p.s.i.g., the product issuing from the coil is quickly cooled and distilled at reduced pressure in the presence of a trace of di-b -naphthol to give methyl 2-methyl-5-methylene-5-phenylvalerate; similarly ethyl methacrylate gives ethyl 2-methyl-5-methylene-5-phenyl valerate, butyl methacrylate gives butyl - 2 - methyl - 5 - methylene - 5 - phenyl - valerate, dodecyl a -butylacrylate gives dodecyl 2 - butyl - 5 - methylene - 5 - phenylvalerate, methyl or ethyl acrylate gives methyl or ethyl 5 - methylene - 5 - phenylvalerate, hexyl acrylate gives hexyl 5 - methylene - 5 - phenylvalerate, octadecyl ethacrylate gives octadecyl 2 - ethyl - 5 - methylene - 5 - phenylvalerate, 2-ethylhexyl methacrylate gives 2-ethylhexyl 2-methyl - 5 - methylene - 5 - phenylvalerate and methacrylic acid gives 2-methyl-5-methylene-5-phenylvaleric acid; (2) a mixture of a -methyl-styrene, ethyl methacrylate and hydroquinone is heated in autoclave and the product is distilled in vacuo to give ethyl 2-methyl-5-methylene - 5 - phenylvalerate; (3) a mixture of methyl 2 - methyl - 5 - methylene - 5 - phenylvalerate, lauryl alcohol and sulphuric acid as catalyst is refluxed, methanol is removed and dodecyl 2 - methyl - 5 - methylene - 5 - phenylvalerate is obtained by distillation in vacuo.  2 - Methyl - 5 - cyclohexyl - caproic acid is obtained by saponifying methyl 2-methyl-5-methylene-5-phenylvalerate with potassium hydroxide to the corresponding acid and hydrogenating the sodium salt of the acid using a Raney nickel catalyst.  2 - Bromo - 2 - methyl - 5 - cyclohexyl - caproic acid is prepared by brominating 2-methyl-5-cyclohexyl-caproic acid using the Hell-VolhardZelinsky method.ALSO:Compounds of formula <FORM:0837220/IV (a)/1> wherein R1 is hydrogen or an alkyl group of 1-4 carbon atoms and R is hydrogen or an alkyl or cycloalkyl group of not over 18 carbon atoms (see Group IV (b), are used as plasticizers for polyvinyl chloride.  Thus a mixture of 2 - ethylhexyl - 21 - methyl - 51 - methylene - 51 - phenylvalerate, polyvinyl chloride and cadmium-barium laurate is milled and formed into a film.  The compounds may also be reacted with phthalic anhydride, glycols or other alcohols and drying or semi-drying oils to produce oil-modified alkyd resins.ALSO:The repellent compositions contain as active ingredient compounds of formula <FORM:0837220/VI/1> wherein R1 is hydrogen or an alkyl group of 1-4 carbon atoms and R is hydrogen or an alkyl or cycloalkyl group of not over 18 carbon atoms (see Group IV(b)).  The compounds may be applied in an oil-base spray carrier or in aqueous emulsions, aerosols or dusts.  The copper salts of the compounds may be used as fungicides and applied as a solution in kerosene.  The compounds obtained by chlorinating the double bond of the methylene group may be used as herbicides and insecticides.