Patent GB-802350-A (GB)
Title: Improvements in or relating to highly unsaturated cyclic compounds
IPC: C07C13/20
Filed: 1957-06-11
Abstract: Coatings are formed by air drying 3,5-dimethylene cyclohexene or 3,5,7-trimethylene cyclo-octene either of which may contain a hydrocarbon substituent (other than one containing an acetylenic linkage) in the 1- and/or 2-position (see Group IV (b)) or compositions containing them.  Conventional drying agents may be added such as oil-soluble organic salts of cobalt, manganese or lead such as octoates, linoleates, naphthenates or resinates, the action of which may be intensified by the addition of an organic peroxide such as benzoyl peroxide.  In examples: (8) 3,5-dimethylenecyclohexene was poured on to a glass plate and allowed to air-dry, a soft film was formed; (9) 3,5-dimethylenecyclohexene containing cobalt 2-ethylhexoate was similarly dried on a steel panel to give a hard film; (10) 3,5,7-trimethylenecyclo-octene containing cobalt 2-ethylhexoate was similarly dried on a glass panel to give a soft film; (11) a portion of a product containing 3,5-dimethylenecyclohexene formed by reacting allene and acetylene in tetrahydrofurane in the presence of nickel acetylacetonate, from which product the tetrahydrofurane had been removed on a steam bath, was treated with cobalt 2-ethylhexoate and flowed out on a steel plate.  A hard glossy film was obtained on exposure to air.ALSO:3,5 - Dimethylenecyclohexene or 3,5,7 - trimethylenecyclooctene either of which may contain a hydrocarbon substituent (other than substituents containing an acetylenic linkage) in the 1- and/or 2-position (see Group IV (b)) may be polymerized at - 80 DEG  to 100 DEG  C. or copolymerized with conjugated dienes, maleic anhydride or styrene. Catalysts may be used such as aluminium chloride or bromide, titanium tetrachloride, tin tetrachloride, sulphuric acid or boron trifluoride.  The monomers also polymerize on oxidative drying, which may be accelerated by the addition of 0.01-2 per cent by weight of an octoate, linoleate, naphthenate or resinate of cobalt manganese or lead, the action of which may be intensified by the addition of benzoyl peroxide.  In the examples: (8) 3,5-dimethylenecyclohexene was poured on to a glass plate and allowed to dry; a soft film was formed; (9) cobalt 2-ethylhexoate was added in small amount to 3,5-dimethylene-cyclohexene and the mixture poured on to a steel panel.  A hard film was formed; (10) 3,5,7 - trimethylenecyclooctene containing a small amount of cobalt 2-ethylhexoate was poured on to a glass panel, a soft film was rapidly formed; (12) 3,5-dimethylenecyclo-hexene was polymerized at 0-5 DEG  C. under the influence of trifluoroacetic acid to give a slightly yellowish solid having a molecular weight (determined cryoscopically) of about 1600; (13) 3,5-dimethylenecyclohexene was polymerized in petroleum ether at - 60 DEG  C. by the action of boron trifluoride to give a white solid; (14) as in (13), titanium tetrachloride replacing the boron trifluoride; (15) 5 g. of 3,5-dimethylene-cyclohexene and 5 g. of maleic anhydride were refluxed in benzene under nitrogen to give a solid and an oily copolymer; (16) 1 ml. of 3,5-dimethylenecyclohexene and 4 ml. of styrene were copolymerized in petroleum ether at -60 DEG C. with titanium tetrachloride to a white solid; (17) equimolar quantities of 3,5-dimethylene cyclohexene and ethylazoformate were refluxed in hexane to give a viscous polymer; (18) 3,5,7-trimethylenecyclooctene was polymerized with boron trifluoride in petroleum ether on warming from -60 DEG  to 0 DEG  C. to a white solid.ALSO:The Specification comprises compounds of the formula <FORM:0802350/IV (b)/1> where R1 and R11 may be the same or different, each representing a hydrogen atom or a hydrocarbon radical other than one containing an acetylenic linkage.  They are prepared by copolymerizing two or three molecules of allene with one molecule of an acetylene R1C­CR11 in the presence of a catalyst comprising a nickel derivative of a weak acid having a dissociation constant below 9 X 10-10 Typical nickel compounds are the cyanide, thiocyanate, hydroxide, ethyl mercaptide, glycinate, borate, dimethylglyoxine and co-ordination compounds or chelates with compounds having an enol form such as ethyl acetoacetate, ethyl beta-methylacetoacetate, ethyl alpha-phenylacetoacetate, methyl alpha-benzylacetoacetate, ethyl 3,5-diketopimelate, methyl benzoylacetate, acetylacetone, 3 - methylpentane - 2,4 - dione, 2 - carbethoxy - cyclopentan - 1 - one, ethyl salicylate, salicylaldehyde, 2-formylcyclohexan-1-one, o-hydroxyacetophenone, ethyl acetonedicarboxylate, and benzoylacetone.  They are used in amounts of 0.005 to 0.05 gram-atom of nickel per mol. of allene. A liquid reaction medium is preferred such as ethyl acetate, methylol, trimethylene sulphone, tetrahydrofurane, acetone, dioxane, benzene, toluene or acetonitrile. Room temperature to 150 DEG  C. may be used at superatmospheric pressure, e.g. allene may be added to the catalyst and diluent as a liquid and then heated to reaction temperature and the acetylene pumped in at 100-300 p.s.i. until the calculated amount has been absorbed.  Calcium carbide may be added to ensure elimination of water.  Steam distillation and/or fractional distillation may be used to recover the products.  The groups R1 and R11 in the starting acetylene if not hydrogen may be alkyl, alkenyl, cycloalkyl or aryl, preferably of not more than 6 carbon atoms and preferably at least one of R1 and R11 is hydrogen. Suitable acetylenes are acetylene, methyl-acetylene, phenylacetylene, monovinylacetylene, ethylacetylene, n-propyl-acetylene, n-butyl-acetylene, isobutylacetylene.  n - hexylacetylene, cyclohexylacetylene, dimethylacetylene and diethylacetylene.  The product dimethylene cyclohexenes can be isomerized to substituted or unsubstituted m-xylenes free from other position isomers.  In the examples: (1) 3,5-dimethylenecyclohexane was recovered by distillation from the reaction product of allene and acetylene in the presence of nickel acetylacetonate in tetrahydrofurane, The product was hydrogenated in glacial acetic acid over a platinum oxide catalyst to a mixture of cis- and trans-1,3-dimethyl-cyclohexanes and isomerized to m-xylene (a) by heating at 80 DEG  C. with palladium on carbon, (b) by refluxing in tert.-butyl alcohol containing potassium tert.-butoxide, and (c) by refluxing in chloroform containing p-toluenesulphonic acid.  Bromination in carbon tetrachloride in the presence of sodium bicarbonate yielded alpha-bromo-m-xylene and alpha, alpha1-dibromo-m-xylene; (2) 3,5 - dimethylene cyclohexene was recovered from the reaction product of allene and acetylene in the presence of nickel cyanide in tetrahydrofurane; (3) nickel ethyl acetoacetate replaced nickel cyanide in (2); (4) 1- and 2-methyl-3,5-dimethylene cyclohexene were recovered as a mixture from the reaction product of allene and methyl-acetylene. Isomerization by refluxing in chloroform containing p-toluenesulphonic acid gave mesitylene and 1,2,4-trimethylbezene; (5) a mixture of 1- and 2-phenyl-3,5-dimethylene-cyclohexene was prepared from allene and phenylacetylene; (6) a mixture of 1- and 2-vinyl-3,5-dimethylenecyclohexene was prepared from allene and monvinylacetylene; (7) from the higher boiling fractions from the product of (1), 3,5,7-trimethylene-cyclo-octene was recovered.