Patent GB-1081282-A (GB)
Title: Bis-benzotriazoles and compositions containing same
Inventor: RANDELL DONALD RICHARD
IPC: C23C22/05
Filed: 1964-08-14
Abstract: Antifreeze, synthetic lubricants, cutting oils and coolant formulations which are used in contact with metal surfaces and are susceptible to deterioration on such contact, contain, as a metal deactivator, a compound of the formula <FORM:1081282/C4-C5/1> wherein X represents a direct link, a C1- 6 straight chain alkylene radical optionally substituted by one or more C1- 4 alkyl groups; a 1,1-cyclohexyl radical; a carbonyl radical; a sulphuryl radical; an oxygen atom or a sulphur atom.  Abrasive compositions for application to a metal surface contain as a tarnish or corrosion inhibitor, one or more compounds of the Formula III above.  Examples 4 and 14 relate to abrasive compositions, an aqueous isopropanol suspension of an abrasive material and are based on a water emulsifiable polish containing an abrasive soap.ALSO:Treatment of a metal or metal alloy surface to inhibit tarnishing or corrosion comprises contacting the surface with a bis-benzotriazole of the formula <FORM:1081282/C6-C7/1> wherein X represents a direct link, a C1- 6 straight chain alkylene radical optionally substituted by one or more C1- 4 alkyl groups; a 1, 1-cyclohexyl radical; a carbonyl radical; a sulphuryl radical; an oxygen atom or a sulphur atom.  Treatment can be effected by 1 dipping, padding or spraying the surface with a solution of the benzotriazole in aqueous organic solvents, 2 condensing the vapour of the compounds on the surface of the metal, 3 wrapping the metal in a packaging material impregnated with the benzotriazoles, 4 polishing the metal surface with an abrasive or non-abrasive polish or 5 incorporating the benzotriazoles in a functional fluid, e.g. lubricants, which are used in the presence of the metal surface.  Examples 2-4, and 13-16 relate to the treatment of copper and cadmium.ALSO:The invention comprises bis-benzotriazoles of the formula <FORM:1081282/C2/1> wherein X represents a C1- 6 straight chain alkylene radical which is substituted by 1 or 2 C1- 4 alkyl groups when the alkylene radical is methylene, or substituted by 1 or more C1- 4 alkyl groups when the alkylene radical contains 2-6 carbon atoms, or unsubstituted when the alkylene radical contains 2-6 carbon atoms; a 1,1-cyclo-alkyl radical of at least 5 carbon atoms, a carbonyl group, a sulphuryl group; an oxygen atom or a sulphur atom.  The compounds can be made by treating a tetra-amino compound of the formula <FORM:1081282/C2/2> with nitrous acid, or with a compound capable of forming nitrous acid under the reaction conditions, in such an amount that only two of the amino groups are diazotized; the benzotriazole is then formed by simultaneous elimination of water.  The compounds in which X is a carbonyl group may also be prepared by reacting the tetrahydrochloride of 3,31,4,41-tetra-amino-benzophenone with sodium nitrite or by controlled oxidation of the corresponding bis-(benzotriazolyl) methane.  The compound in which X is a sulphuryl group may also be prepared by oxidation of bis-(benzotriazolyl-5) sulphide.  The bis-benzotriazoles are used as tarnish and corrosion inhibitors (see Divisions C4, C5 and C7). Examples describe the preparation of compounds in which X is (5) carbonyl, (6) oxygen, (7) sulphuryl, (10) ethylene, (11) 1,1-cyclohexylidene and (12) 2,2-propylene radicals. The amines of the Formula XII above are made by nitrating the diamine of the formula <FORM:1081282/C2/3> optionally while protecting the amine groups by acylation, and then reducing the resulting amine of the formula <FORM:1081282/C2/4> either catalytically or using HCl and Fe or Sn.  4,41-Diamino-3,31-dinitrobenzophenone can be prepared by nitrating 4,41-dichlorobenzophenone to give 3,31-dinitro-4,41-dichlorobenzophenone benzophenone which is heated with ammonia at an elevated temperature to given the aminonitro compound.  Bis - benzotriazole and bis - (benzotriazolyl)-methane can be made by methods analogous to those used for compounds of the Formula III, viz. from the corresponding tetra-amines which are prepared from the diamino-dinitro compounds.  3,31 - Dinitro - 4,41 - diamino -diphenylmethane can be prepared by rearrangement of N,N1 - methylene - bis - o - nitroaniline (Examples I and 8).