Patent GB-1140529-A (GB)
Title: Preparation of organosilicon compounds
IPC: C07F7/08
Filed: 1965-12-24
Abstract: 1,140,529. Organosilanes and organosiloxanes. UNION CARBIDE CORP. 24 Dec., 1965 [29 Dec., 1964], No. 54824/65. Headings C3S and C3T. [Also in Division D1] Organosilicon compounds are obtained by reacting a hydrosilicon compound, i.e. a compound containing at least one silicon to hydrogen bond, e.g. a hydrosilane or a hydrosiloxane, with a compound containing an active hydrogen atom in the presence of a positive halogen compound, i.e. wherein the halogen atom is at the positive end of a dipole and the residual portion is nucleophilic, in which the halogen has an atomic weight greater than 19, and an acid acceptor. The reaction may be effected in an inert solvent, e.g. aliphatic and aromatic hydrocarbons, ketones, esters, nitriles and ethers, at a temp. of - 100 to +200 C. at pressures above, at or below atmospheric pressure. Suitable hydrosilanes are those of formula R x SiH 4-X  where R is a monovalent hydrocarbon group, a monovalent functionally substituted hydrocarbon group or a monovalent functional group and x is 1 to 3 inclusive. The monovalent hydrocarbon groups may be the same or different aliphatic or aromatic groups which may be saturated or olefinically unsaturated. Specified functional groups are alkoxy, aryloxy, acyloxy, oxirano, cyano, fluoro, amino, amido, hydroxy, carboxy and acyl groups. Suitable hydrosiloxanes are homopolymers or copolymers comprising units of the formula . where a is 1 to 3 inclusive, b is 0 to 2 inclusive and (a+b) is 1 to 3 inclusive. The compound containing an active hydrogen atom may be a carboxylic acid, e.g. mono- and poly-carboxylic acids, an amine, e.g. primary and secondary alkyl, aryl and heterocyclic amines, amercaptan, e.g. t-butyl and ethyl mercaptan, a thioacid, e.g. thioacetic and thiobenzoic acids, a compound containing hydroxyl groups such as water, alcohols, polyols, silanols and siloxanols, or substrata such as natural and synthetic fibres and glass. Suitable positive halogen compounds include alkyl and acyl hypohalides, N-halo-amines, -amides and -imides, 1,3-dichloro - 5,5 - dimethylhydantoin, bromoisocyanuric acid, 1-haloalkynes, α-halocarbonyl compounds, halonitromethanes, halocyanomethanes, halomethanes, haloacylmethanes, activated haloaromatic compounds, nitryl halides, sulphenyl halides, molecular halogens and interhalogen compounds, inorganic hypohalites and oxyalkylene hypohalites of the formula R<SP>111</SP>O(C n H 2n O) x COX where X is halogen, having an atomic weight greater than 19, R<SP>111</SP> is X or R (as defined above), n is from 2 to 4 and x is from 1 to about 100. Acid acceptors specified are pyridine, picoline, collidine, quinoline, sodium acetate, t-butylacetate and magnesium. The invention also includes a composition capable of being cured at room temperature which comprises a hydrosilicon compound convertible to an elastomer, an active hydrogen atom containing compound, a positive halogen compound, wherein the halogen atom has an atomic weight greater than 19, and an acid acceptor. The composition may contain other conventional additives such as fillers, pigment, antioxidants and solvents. Examples are given in which siloxane gums are cured.