GB677199A - Improvements in or relating to the preparation of organic compounds involving chain reaction mechanisms - Google Patents

Abstract

The preparation of organic compounds from dissimilar reactants capable of reacting through a chain reaction mechanism in the presence of free atoms or free radicals is effected by subjecting a mixture of the reactants with a linear polymer (including cellulose derivatives and condensation resins) having a molecular weight of at least 104 to an agitation treatment sufficient to degrade the polymer and thus form the free radicals necessary to initiate the desired reaction. The agitation, which may be carried out in the presence or absence of a solvent or diluent, may consist of intensive shaking, high-speed stirring, milling, kneading, grinding, the use of gear and piston pumps, treatment with ultrasonic radiation or passage through filters and capillaries. Suitable linear polymers, the molecular weight of which may range up to 9 X 106 but is preferably between 7.5 X 104 and 7 X 106, are cellulose esters and ethers, linear alkyd resins, linear polyamides and polymers of the carbonic acid esters of unsaturated diols (examples of all of which are given), linear phenol-aldehyde condensation products, and particularly homopolymers, copolymers and interpolymers of polymerizable olefinic compounds (e.g. of unsaturated acids and their derivatives, tetrahaloethylenes, butadienes, vinyl aromatic compounds and vinyl esters, ethers and ketones, and especially of vinylidene halides, acrylic acid and a -alkylacrylic acids in which the alkyl radical contains 1-4 carbon atoms, their esters with alkanols containing 1-6 carbon atoms in the molecule, and their nitriles, vinyl esters of saturated monocarboxylic acids containing 1-6 carbon atoms in the molecular and of halogen acids, isobutylene, styrene and a -methylstyrene). Chain reactions to which the process is applicable include: (a) addition reactions of halogens, hydrogen halides, polyhalogenated saturated aliphatic hydrocarbons, mercaptans, phosphorus trichloride or alkali metal bisulphites with ethylenically unsaturated organic compounds preferably containing at least one CH2=C< group (especially propene, butene-1, octene-1, styrene, ethyl acrylate, allyl alcohol, allyl chloride or vinyl chloride); (b) substitution halogenations (especially sidechain halogenation of araliphatic compounds); (c) sulphonation of hydrocarbons with sulphuryl chloride (usually in the side chain in the case of araliphatic hydrocarbons); (d) carboxylation of hydrocarbons by the action of oxalyl chloride; (e) reaction of carbon disulphide with hydrocarbons to produce thio-substituted products; (f) oxidation reactions (e.g. of alcohols to aldehydes, aldehydes to acids, acids to peracids, hydrocarbons to peroxides or sulphites to sulphates); (g) telomerization reactions, e.g. of olefines with aliphatic halogen-containing compounds, with hydrogen chloride or with saturated organic compounds containing only carbon, hydrogen and oxygen (e.g. alcohols, aldehydes, ketones, acids, esters, orthoesters, acid anhydrides, ethers or acetals). In examples: (1) carbon tetrabromide and styrene are shaken with polystyrene and carbon tetrachloride to produce 1 : 1 : 1 : 3-tetrabromo-3-phenylpropane; (2) carbon tetrachloride and octene-1 are rapidly stirred with polyisobutylene to form 1 : 1 : p 1 : 3 - tetrachlorononane; (3) toluene and bromine are shaken with polyisobutylene to give benzyl bromide; (4) oxygen is bubbled through a rapidly stirred mixture of cumene, polyisobutylene and cyclohexane, producing cumene hydroperoxide; (5) cyclohexane is chlorinated by shaking it with chlorine and polyisobutylene; (6) a mixture of phenyl mercaptan, styrene and methyl methacrylate polymer is repeatedly passed through a narrow orifice, yielding 1-phenyl-2-phenylmercaptoethane. Lists of additional starting materials for the various types of reaction enumerated above are given.