Patent GB-776660-A (GB)
Title: Sulphides and polysulphides, methods for preparing same and lubricant compositions containing same
IPC: C10M137/10
Filed: 1953-12-23
Abstract: The invention comprises as new compounds the bis - (tri - organophosphorus) sulphides and polysulphides having the structure [(RO)(R1O) P(S)S.R11-]2Sy wherein R and R1 are the same or different hydrocarbon radicals of from 2 to 30 carbon atoms, R11 is a non-aromatic, non-acetylenic divalent organic radical of at least 2 carbon atoms, and y has an average value within the range from 1 to about 3.  The hydrocarbon radicals R and R1 may be alkyl, saturated cycloaliphatic, aromatic, aralkyl, or alkaryl radicals having 2 to 30 carbon atoms and R11 is preferably a hydrocarbon radical, which may, however, be substituted, e.g. by a halogen atom, nitro group, or carboxylic ester radical.  The compounds may be prepared by the following methods in which R, R11 and y are as defined above and the R groups may be the same or different, Q is hydrogen or an organic radical free from reactive substituent groups, Q1 is a divalent organic radical free from reactive substituents, M is a metal, e.g. an alkali metal, and t is an integer: (a) reacting two mols. of a salt of the formula (RO)2P(S).SM with one mol. of a compound (Cl-R11-)2Sy with elimination of metal chloride; (b) reacting two mols. of a compound (RO)2P(S)SH with one mol. of a compound (Cl-R11)2Sy with elimination of hydrogen halide; (c) addition reaction of two mols. of a compound (RO)2P(S)SH with one mol. of a compound [CH(=CHQ)-Q1-]2Sy to form the product [(RO)2P(S).S.CH(CH2Q)-Q1-]2Sy; (d) by reacting two mols of a compound (RO)2 P(S).S.(CHQ)t-CH2-CH = CHQ with one mol. of a sulphur halide, e.g. S2Cl2 to form the compound [(RO)2.P(S).S.(CHQ)t-CH(-CH=CHQ) -]2S2 with elimination of hydrogen halide; and (e) by reacting 2 mols. of a compound (RO)2P(S).Cl with one mole of a compound (HSR11-)2Sy to form the compound [(RO)2P(S).SR11-]2Sy with elimination of hydrogen halide.  Bromine may replace chlorine in the halogen-containing starting material used in methods (a), (b), (d) and (e).  Method (a) is preferably carried out by heating the reactants at reflux temperature which may be in the range of about 30 DEG  to 300 DEG  C. and additional sulphur may be present during the reaction to increase the amount of sulphur in the sulphide or polysulphide linkage.  The reaction is preferably carried out in the presence of a solvent, e.g. benzene, acetone, or a lower molecular weight alcohol.  The solvent is preferably one in which the metal halide formed is insoluble.  Method (b) may be carried out by heating the reactants at reflux temperature which may be from 30 DEG  to 300 DEG  C., e.g. 50 DEG  to 150 DEG  C., and the reaction is usually carried out in the presence of an inert solvent, e.g. benzene or naphtha.  It is also preferred to carry out the reaction in the presence of an HCl-sequestering agent e.g. an amine such as pyridine or dimethylaniline.  Method (c) may also be carried out at 30 DEG  to 300 DEG  C., e.g. at 50 DEG  to 150 DEG  C., and in the presence or absence of a solvent such as benzene or toluene. Method (d) may be effected by heating the reactants at between 30 DEG  and 250 DEG  C., e.g. at between 70 DEG  and 150 DEG  C., and the reaction can take place in the presence or absence of a solvent and if desired in the presence of an HCl-sequestering agent.  Method (e) may be effected by heating the reactants at from 30 DEG  to 250 DEG  C. and preferably in the presence of an HCl-sequestering agent, e.g. an amine such as pyridine or dimethylaniline.  The reaction may also be carried out in the presence of a liquid diluent such as benzene or naphtha, which is insoluble to the by-product amine hydrochloride.  Examples are given for the production of: (1) [(n-hexyl O)2P(S)S.-C5H10-]2\t S2 by reacting amylenes with S2Cl2 to form (ClC5H10-)2S2 and then reacting the latter with the sodium salt of di-n-hexyl dithiophosphoric acid which is obtained by reacting 4 mols. of n-hexyl alcohol with P2S5 at 100 DEG  C., dissolving the product in ethanol and neutralizing with aqueous NaOH; (2) [ [(wax-phenyl-O-)2PSS-C5H10-]2S2 by reacting the compound (ClC5H10-)2S2 with the sodium salt of di-(wax-phenyl) dithiophosphoric acid which is prepared by reacting wax-substituted phenol with P2S5 at 130 DEG  C. and neutralizing the product with sodium methylate; (3) [(4-methyl-2-pentyl-O-)2PSS-C5H10-]2S by reacting the compound (ClC5H10-)2S with the sodium salt of di - (4 - methyl - 2 - pentyl) dithiophosphoric acid which is obtained by reacting 4-methyl-pentanol-2 with P2S5 and treating the product, dissolved in methanol, with sodium methylate; (4) [(2 - ethylhexyl-O)2PSSC8H16-]2S by reacting di-isobutylene with SCl2 to form the compound (ClC8H16-)2S which is then reacted with the sodium salt of di-(2-ethylhexyl) dithiophosphoric acid, the latter being obtained by reacting 2-ethylhexanol with P2S5 at 100-110 DEG  C. and then neutralizing the product, dissolved in ethanol, with aqueous NaOH; (5) [(2-ethylhexyl-O)2PSS-C8H16-]2S2 by reacting di-isobutylene with S2Cl2 to form the compound (ClC8H16-)2S2 which is then reacted with the sodium salt of di-(2-ethylhexyl) dithiophos8 phoric acid; (6) [(4-methyl-2-pentyl-O-)2PSS-C8H16-]2S by reacting the compound (ClCH16-)2S with the sodium salt obtained by neutralizing di-(4-methyl-2-pentyl) dithiophosphoric acid, dissolved in ethanol, with aqueous NaOH; (7) [(2-ethyl-hexyl-O-)2PSS-C19H36 O2-]2S2 by reacting methyl chlorostearate disulphide with the appropriate sodium dithiophosphate, in the presence of cuprous oxide as catalyst; (8) [(2-ethyl-hexyl-O-)2PSS-C19H36 O2-]2S by a process as in (7) except that methyl chlorostearate monosulphide (obtained by reacting methyl oleate with SCl2) is used; (9) [(2 - ethylhexyl-O-)2PSS-C3H5Cl-]2S by reacting the appropriate sodium dithiophosphate with bis-(dichloropropyl) sulphide (obtained by reacting allyl chloride (2 mols.) with SCl2 (1 mol.)]; (10) [((4-methyl-2-pentyl-O-)2 PSS-)2C3H5-]2S by reacting 4 mols. of th appropriate sodium dithiophosphate with 1 mol. of bis-(dichloropropyl) sulphide; (11) [(4-methyl - 2 - pentyl - O-)2PSSC3H5Cl-]2S by a process as in (9) except that the sodium salt of di - (4 - methyl - 2 - pentyl) dithiophosphoric acid is used; (12) [(2 - ethylhexyl - O-)2-PSS-C8H15Cl-]2S by reacting bis-(dichloro diisobutyl) sulphide (obtained by reacting chloro-di-isobutylene with SCl2) with the appropriate sodium dithiophosphate; (13) [(4-methyl-2-pentyl-O-)2PSSC8H15Cl-]2S by a process as in (12) except that the sodium salt of di-(4-methyl-2-pentyl) dithiophosphoric acid is used; (14) [(wax-phenyl-O-)2PSS-C5H10-]2S by reacting the compound (ClC5H10-)2S with the appropriate dithiophosphoric acid in the presence of naphtha and pyridine; (15) [(2-ethyl - hexyl - O-)2PSS - C8H16-]2S by reacting bis-(di-isobutenyl) sulphide (obtained by reacting chlorodi-isobutylene with sodium sulphide in the presence of water and a wetting agent) with d-2-ethylhexyl dithiophosphorc-acid by method (c); (16) [(2 - ethyl - hexyli O-)2PSSC4H6-]2S2 by reacting di-(2-ethyl-hexyl) butenyl dithiophosphate (prepared by passing 1,3-butadiene through di-2-ethylhexyl-dithiophosphoric acid in toluene solution at 100 DEG  C.) with S2Cl2; (17) [(2-ethylhexyl-O-)2PSS-C4H6-)2S by a process as in (16) except that SCl2 is used; (18) [(RO)2PSS-C4H6]2S2 wherein R is a radical derived from a mixture of alcohols, by reacting a mixture of capryl, 4-methyl-2-pentyl and n-hexyl alcohols with P2S5, treating the product with 1,3-butadiene to prepare the butenyl ester and reacting the latter with S2Cl2; (19) [(isononyl-O-)2PSS-C4H6-]2S2 by treating di(isononyl)-dithiophosphoric acid with 1,3 butadiene to form di-(isononyl) butenyl dithiophosphate which is then reacted with S2Cl2; (20) [(RO)2PSS-C4H6]2S by a process as in (18) but using SCl2. The products are useful as additives for lubricating oils (see Group III).  The compounds (Cl-R11-)2Sy used in methods (a) and (b) may be obtained by reacting, e.g. at - 15 DEG  C. to 100 DEG  C., an unsaturated organic compound with a sulphur halide, e.g. sulphur mono- or dichloride.  Several unsaturated compounds which may be used are specified including hydrocarbons, e.g. olefines, di-olefines, terpenes, and olefin polymers, halogen-substituted hydrocarbons and unsaturated carboxylic esters, Unsaturated compounds containing halogen substituents and nitro groups may also be used.  Sulphur bromides can also be used instead of sulphur chlorides.  A mixture formed by heating S2Cl2 with sulphur at 130-140 DEG  C. may also be used.  The di-organo dithiophosphoric acid compounds can be prepared by reacting a phosphorus sulphide, especially P2S5 with an organic hydroxy compound which may be an alcohol or phenol, e.g. ethyl, isopropyl, butyl, amyl, 4-methyl-pentyl-2, hexyl, heptyl, methyl-cyclohexyl, 2-ethyl hexyl, octyl, ethylcyclohexyl, nonyl and lauryl alcohols, phenol, butyl phenol, amyl phenol, diamyl phenol, tert. octyl phenol, wax phenols and naphthols.  The alkali metal salts of these acids can be obtained by reacting the acid with an alkali metal hydroxide or alcoholate, conveniently in an alcohol, e.g. methanol, solution.  The salts may also be obtained by reacting the acid with a concentrated aqueous solution of the alkali metal hydroxide at elevated temperature or with alkali metal shavings, e.g. sodium shavings.  The unsaturated sulphides of the type (Q-CH = CH-Q1-)2Sy used in method (c) can be prepared by reacting, e.g. at 30-300 DEG  C., an appropriate halogen-substituted unsaturated organic compound with a sodium sulphide.  Several halogen-substituted compounds are specified including halogen-substituted olefins, olefin polymers, di-olefines and halogen-substituted fatty acid esters, e.g. halogen substituted methyl oleate.  The unsaturated tri-organo phosphorus compound used in method (d) may be obtained by reacting about one mol. of a diester of dithiophosphoric acid with about one mol. of an unsaturated organic compound containing at least