Patent GB-580366-A (GB)
Title: Manufacture of copper mercaptides
Filed: 1943-11-08
Abstract: Copper mercaptides, suitable for colouring mineral and other oils and solvents such as benzene, hexane, paraffin oil, ether, alcohol or dioxane, are obtained by the reaction, advantageously in absence of air and in some cases in presence of a reducing agent, of a monocyclic or bicyclic terpene mercaptan with copper or a copper salt at room temperature or the temperature attained during this reaction. The reaction may be effected with the use of a solution of the mercaptan in a solvent such as the original terpene, ether, benzene, toluene, ligroin, kerosene, lubricating oil or a low boiling naphtha. The products are specially suitable for incorporation in lubricating oils to minimize bearing corrosion.  Examples relate to the preparation of the copper mercaptides of (1), (9), (10) and (11) a-pinene, (2) b -pinene, (3) dipentene, (4) terpinolene, (5), menthene, (6) crude camphene, (7) camphene of b.p. 115-118 DEG C. at 25mm., (8) camphene of b.p. 122-123 DEG C. at 25mm., by the reaction, in some cases in the presence of sodium hydrosulphite, of cuprous chloride in aqueous ammonia with the terpene mercaptan.  The use of mercaptans from mixtures of terpenes such as those of pine oil, turpentine and camphor oils is also specified.ALSO:Copper mercaptides, suitable for colouring mineral and other oils and solvents such as benzene, hexane, paraffin oil, ether, alcohol or are obtained by the reaction, advantageously in absence of air and in some cases in presence of a reducing agent, of a monocyclic or bicyclic terpene mercaptan,with copper or a copper salt at room temperature or the temperature attained during this reaction.  The reaction may be effected with the use of a solution of the mercaptan in a solvent such as the original terpene, ether, benzene, toluene, ligroin, kerosene, lubricating oil or a low boiling naphtha.  The products are specially suitable for incorporation in lubricating oils to minimize bearing corrosion. Examples relate to the preparation of the copper mercaptides of (1), (9), (10) and (11), a -pinene, (2) b -pinene, (3) dipentene, (4) terpinolene, (5) menthene, (6) crude camphene, (7) camphene of c.p. 115-118 DEG  C. at 25 mm., (8) camphene of c.p. 122-123 DEG  C. at 25 mm., by the reaction, in some cases in the presence of sodium hydrosulphite, of cuprous chloride in aqueous ammonia with the terpene mercaptan.  The use of mercaptans from mixtures of terpenes such as those of pine oil, turpentine and camphor oils is also specified.  Monocyclic or dicyclic terpene mercaptans are obtained (a) by heating the terpene with sulphur at 75-200 DEG  C. and simultaneously or subsequently reducing the product with hydrogen at 100-300 DEG  C. under pressure, preferably 300-700 lbs. per sq. in. with or without the use of an organic solvent such as benzene, toluene, xylene, petroleum ether or ligroin, in the presence of a hydrogenation catalyst such as reduced nickel or the sulphides and polysulphides of metals of Groups IV, VI and VIII of the Periodic Table, e.g. cobalt, nickel, iron, molybdenum, tungsten, chromium, lead, palladium, tin and vanadium, or (b) by treating the terpene with hydrogen sulphide, e.g. at 40-200 DEG  C. preferably under superatmospheric pressure and conveniently in the presence of an acid catalyst, e.g. sulphuric acid.