GB1575202A

GB1575202A - Azathiapentalenes and their use as lubricating oil additives

Info

Publication number: GB1575202A
Application number: GB52636/75A
Authority: GB
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1977-01-28
Filing date: 1977-01-28
Publication date: 1980-09-17

Description

(54) AZATHIAPENTALENES AND THEIR USE AS LUBRICATING OIL ADDITIVES (71) We, EXXON RESEARCH AND ENGINEERING COMPANY, a Corporation duly organised and existing under the laws of the State of Delaware, United States of America, of Linden, New Jersey, United States of America, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to certain azathiapentalenes which can be used as lubricating oil additives. When used as such the azathiapentalenes of this invention act as corrosion inhibitors, antioxidants and anti-wear agents.

According to this invention novel azathiapentalenes have the general formula: where

Z is O or S Q is -SR or -NHR4 when Z is S or -R5 or -NIIR4 when Z is O R is hydrocarbyl and R', R2, R4 and R5 are the same or different and are hydrogen- and carbon-containing groups, and R3 is hydrogen or a hydrogen- andcarbon-containing group.

Regarding the group Y, R1, R2, R4 and R5 are the same or different and are preferably hydrogen- and carbon-containing groups, especially hydrocarbyl groups (i.e. a group containing only hydrogen and carbon atoms). Although R' and R3 can be alkyl groups or alkenyl groups (e.g. C, to C18 alkyl groups), it is preferred that R' and R3 be aromatic groups, especially phenyl. They could however be for example alkaryl groups such as phenyl groups having one or more C, to C,8 alkyl substituents.

The groups R, R2 and R5 which may be the same or different, are preferably hydrocarbyl groups. Particularly preferred R, R2 and R5 groups are alkyl groups, although they can be alkenyl, aryl, alkaryl or aralkyl groups. Especially preferred are azathiapentalenes where R, and R5 are C, to C,8 alkyl groups, e.g. methyl, ethyl, n-propyl, n-butyl, iso-butyl, n-hexyl, iso-octyl, n-decyl or n-dodecyl.

Especially preferred examples of R2 are methyl and ethyl.

The azatrithiapentalenes (i.e. Z=S) can be prepared in different ways according to whether Q is -SR or -NHR4. When Q is -SR a 5-amino-1,2 dithio 3-thione is reacted with carbon disulphide in the presence of a base (e.g. Et3N) followed by reaction with a halohydrocarbon (e.g. RX) to give the desired 3-aza 1,6,6a-trithiapentalene.

Thus,

where X is a halogen atom.

The base which is used in this reaction is preferably an amine, e.g. a trialkylamine such as triethylamine. Approximately stoichiometric quantities of reactants should be used and the reaction between the 1,2-dithiole-3-thione and carbon disulphide can take place at a temperature of 30 to 700 C, e.g. about 50"C.

In the second stage of the reaction an approximately stoichiometric quantity of halohydrocarbon should be added and it is preferred that the reaction mixture be cooled to ambient temperature before this addition of reactant. The halohydrocarbon RX is preferably an alkyl halide, especially an alkyl iodide or bromide such as methyl iodide or butyl bromide. The reaction mixture is preferably agitated, for a period of time about 30 minutes generally being sufficient and water then added. The desired 3-aza-1,6,6a Slv-trithiapentalene can be obtained by extracting the resulting mixture preferably with benzene.

When Q is -NHR4 a 5 - amino - 1,2 - dithiole - 3 - thione is reacted with an isothiocyanate (R4NCS) in the presence of a base (e.g. Et3N) followed by reaction with a halohydrocarbon (RX) to give the desired 3-aza-1,6,6a,SiV-trithiapentalene.

Thus,

This reaction is similar to the above described reaction and similar bases and halohydrocarbons can be used. The isothiocyanate (R4NCS) is added to approximately stoichiometric quantities of the 1,2 - dithiole - 3 - thione and base dissolved in a solvent such as dimethyl formamide. After stirring the reaction mixture an approximately stoichiometric quantity of halohydrocarbon, such as methyl iodide or octyl bromide is added and the reaction mixture is agitated, for about 30 minutes. Water is then added and the resulting solution is extracted preferably with benzene, to obtain the desired 3- aza - 1,6,6aS'V- trithiopentalene.

As an alternative one can simply add the halohydrocarbon to the already prepared substituted thiourea, e.g. an N - hydrocarbyl - N' - (3 - thione - 1,2,4 dithiazyl - 5) - thiourea and then treat with base.

The 1 - oxa - 3 - aza - dithiapentalenes (i.e. Z=O) can be prepared in different ways according as to whether Q is --R5 or -NHR4.

When Q is -NHR4 a 5 - amino 1,2 - dithiole - 3 - thione is reacted with an isocyanate (R4NCO) in the presence of a base (e.g. Et3N) followed by reaction with a halohydrocarbon (RX) to give the desired 1 - oxa - 3 - aza dithiapentalene.

Thus,

Approximately stoichiometric quantities of the 1,2 - dithiole - 3 - thione and isocyanate (R4NCO) are reacted in a solvent such as dimethyl formamide in the presence of a base, typical and preferred bases being the same as in the previous reactions. A salt is obtained and the halohydrocarbon (e.g. methyl iodide) added.

This addition results in the precipitation of the desired 1 - oxa - 3 - aza dithiapentalene from the solution.

As an alternative one can simply add the halohydrocarbon to the already prepared substituted urea, e.g. an N - hydrocarbyl - N' - (3 - thione - 1,2,4 dithiazyl - 5) urea and then treat with base.

When Q is --R5 a 5 - amino - 1,2 - dithiole - 3 - thione is reacted with an acyl halide or acid anhydride. The product obtained is then reacted with a halohydrocarbon and a base to give the desired 1 - oxa - 3 - aza - dithiapentalene.

Thus,

Approximately stoichiometric quantities of the 1,2 - dithiole - 3 - thione and the acyl halide or acid anhydride are reacted. Usually the acyl halide (R5COX) or acid anhydride (R5CO)2O is added dropwise to the thione dissolved in a solvent such as pyridine. It is preferred that the acyl halide or acid anhydride be aliphatic such as an oleyl, stearyl or palmityl halide, or acetic or propionic anhydride. The 5 - acylamido - 1,2 - dithiole - 3 - thione which may be obtained by extraction with for example chloroform is then added to a base such as a solution of sodium methoxide in methanol. The alkyl halide (e.g. methyl iodide dissolved as methanol) is then added and the resulting suspension stirred and allowed to stand. The desired 1 - oxa - 3 - diphiapentalene can then be obtained by extraction.

Some of the preferred azathiapentalenes of this invention are: 2,5 - dibutylmercapto - 4- carbomethoxy - 3 - aza - l,6,6aS1V - trithiapentalene 2,5 - dibutylmercapto - 4 - phenyl - 3 - aza - 1,6,6aSlV - trithiapentalene 2 - anilino - 4 - carbomethoxy - 5 - methylmercapto - 3 - aza - 1,6,6aS'V trithiapentalene 2 - anilino - 4 - phenyl - 5 - n - octylmercapto - 3 - aza - l,6,6aSlV - trithiapentalene 2 - anilino - 4 - phenyl - 5 - n - octylmercapto - 3 - aza - 1 - oxa - 6,6aSlV dithiapentalene 2 - anilino - 4 - carbomethoxy - 5 - n - octylmercapto - 3 - aza - I - oxa 6,6aS'' - dithiapentalene 2 - butylamino - 5 - methylmercapto - 4 - phenyl - 3 - aza - 1 - oxa - 6,6aSlV - dithiapentalene 2 - heptylamino - 5 - methylmercapto - 4 - phenyl - 3 - aza - 1,6,6aS'' trithiapentalene 2 - anilino - 5 - n - octylmercapto - 3,4 - diaza - I - oxa - 6,6aSlV - dithiapentalene 4 - carbomethoxy - 3 - heptadec - 8 - ene - 5 - methylmercapto - 3 - aza 1 - oxa - 6,6aSlV - dithiapentalene.

The azathiapentalene of this invention may be added to lubricating oils where they act as corrosion inhibitors, antiwear agents and antioxidants.

The azathiapentalene may be diluted with lubricating oil so that it is present in a lubricating oil composition as a minor proportion by weight, e.g. 0.01 to 10 wt V based on the total weight of the lubricating oil composition.

The lubricating oil is usually a mineral lubricating oil but it may for example be an oil ranging from petroleum oil to SAE 30, 40 or 50 lubricating oil grades or be a castor oil, fish oil or an oxidised mineral oil.

Alternatively the lubricating oil can be a synthetic ester lubricating oil and these include di-esters such as dioctyl adipate, dioctyl sebacate, didecyl azelate, didecyl adipate, didecyl succinate, didecyl glutarate and mixtures thereof.

Alternatively, the synthetic ester can be a polyester such as that prepared by reacting polyhydric alcohols such as trimethylol propane and pentaerythritol with monocarboxylic acids such as butyric acid to give the corresponding tri- and tetraesters. Also complex esters may be used, such as those formed by esterification reactions between a carboxylic acid, a glycol and an alcohol or a monocarboxylic acid.

The lubricating oil composition may contain other additives for example dispersants such as the reaction product of polyisobutenyl succinic anhydride with tetraethylene pentamine and the reaction product of polyisobutenyl succinic anhydride with pentaerythritol; antiwear agents such as zinc dialkyldithio phosphate (ZDDP); antioxidants such as phosphorus pentasulphide treated alpha pinene, p,p - dioctyl - diphenylamine and 2,6 - di - t - butyl phenol; and viscosity modifiers such as ethylene-propylene copolymers.

Alternatively, the azathiapentalene may be added to a fuel oil, for example a petroleum fuel oil, e.g. a diesel fuel. Usually it is present as a minor proportion by weight.

The present invention is illustrated by the following examples 1 to 10, 12 and 13.

Example 1 2,5 - Dibutylmercapto - 4 - carbomethoxy - 3 - aza - 1,6,6aSiV - trithiapentalene To 5 - amino - 4 - carbomethoxy - 1,2 - dithiole - 3 - thione (10.35 g) in dimethylformamide (100 ml) was added triethylamine (6.19). The solution was heated to 500C and carbon disulphide (4.6 g) added dropwise. After ten minutes butyl bromide (13.7 g) was added and the solution stirred for thirty minutes at 500C.

Water (500 ml) was added and the solution extracted with toluene (3x200 ml). The organic extracts were washed with water and dried over magnesium sulphate.

Removal of the solvent gave a red oil which was chromatographed on silica.

Elution with toluene gave the trithiapentalene (10.1 g, 51%) as a red oil, m/e 395 (M+).

Example 2 2 - 5 - Dibutylmercapto - 4 - phenyl - 3 - aza - l,6,6aSlV - trithiapentalene.

To 5 - amino - 4 - phenyl - 1,2 - dithiole - 3 - thione (11.25 g) in dimethylformamide (50 ml) was added triethylamine (5.1 g). After stirring for ten minutes carbon disulphide (4.6 g) was added and the temperature raised to 500C.

After an hour, butyl bromide (13.7 g) was added and the solution allowed to stand overnight. Water (300 ml) was added and the aqueous layer extracted with toluene (2x 150 ml). The combined organic layers washed with water (5x 100 ml) and dried over magnesium sulphate. Removal of the solvent gave a red oil which was chromatographed on silica. Elution with toluene gave the trithiapentalene (12.1 g) as a red oil m/e 415 (M+).

Example 3 2 - Anilino - 4 - carbomethoxy - 5 - methylmercapto - 3 - aza - 1,6,6aS'V - trithiapentalene To 5 - amino - 4 - carbomethoxy - 1,2 - dithiole - 3 - thione (1.035 g) in dimethylformamide (10 ml) was added triethylamine (0.84 g) followed by phenylisothiocyanate (0.73 ml).

After stirring for ten minutes at room temperature methyl iodide (0.62 ml) was added and the solution stirred for a further thirty minutes. Water was then added and the solution extracted with benzene. After drying over magnesium sulphate the benzene was removed and the residue was chromatograhped on alumina. Elution with ether gave the trithiapentalene (1.085 g, 61%) which was obtained from cyclohexane/benzene (4:1) as orange prisms of melting point 134--135"C.

(Found: C, 44.0; H, 3.4; N, 7.9. C,3H,2N202S4 requires C, 43.8 H, 3.4; N, 7.9); T (CDCl3) 1.83 (1H, NH), 2.3-2.9 (5H multiplet, aromatic), 6.08 (2H, CO2CH3), 7.43 (2H, s, SCH3); m/e 370 (M+).

1 - Phenyl - 2,5 - dimethylmercapto - 4 - carbomethoxy - 1,3 - diaza 6,6aSlV - dithiapentalene is also formed in this reaction (15%). This product is separated from the above product by first eluting with benzene on an alumina column.

Example 4 2 - Anilino - 4 - carbomethoxy - 5 - n - octylmercapto - 3 - aza - l,6,6aSlV trithiapentalene 5 - Amino - 4 - carbomethoxy - 1,2 - dithiole - 3 - thione (20.7 g) was dissolved in dimethylformamide (250 ml) and triethylamine was added dropwise.

After stirring for ten minutes phenylisothiocyanate (13.5 g) was added and the solution stirred for a further ten minutes n-octyl bromide (19.3) was added and the solution stirred at 500 for two hours. Water was then added and the solution extracted with ether (3x200 ml). The ethereal solution was then washed with water (3x 10 ml) and dried over magnesium sulphate. The ether was removed in vacuo to give an orange solid (yield 38.5 g, 85%). This was recrystallised from ethanol to give red crystals m.p. 104--1050) (Found: C, 52.9; H, 5.8; N, 6.3; S, 27.9: C20H28N2O2S4 requires C, 52.8; 5.7; N, 6.2; S, 28.2%), t (CDCl3) 1.63 (1H, NH), 2.3-3.0 (5H, aromatic), 6.05 (3H, s, OCH3) 6.88 (2H, t, CH2S), 8-9.2 (17H, alkyl); m/e 454 (M+).

Example 5 2 - Anilino - 4 - Phenyl- 5 - octylmercapto - 3 - aza - 1,6,6aSlV - trithiapentalene To 5 - amino - 4- phenyl - 1,2- dithiole - 3 - thione 533.5 g) in dimethylformamide (200 ml) was added triethylamine (10.2g) and the solution stirred for ten minutes. Phenyl isothiocyanate (13.5 g) was added and the solution stirred for an hour. Octyl bromide (19.3 g) was added and the solution allowed to stand overnight. Water was added and the solution extracted with ether (3x200 ml).

The ether solution was washed with water and dried over magnesium sulphate.

Removal of the solvent gave an orange oil which solidified on standing (yield, 40.5 g, 86%). The trithiapentalene crystallised from ethanol as orange prisms m.p. 1191200C (Found: C, 61.0; H, 6.1, N, 5.9,S,25.7%: C24H28N2S4 requires C, 61.0; H, 5.9; N, 5.9%) T (CDCl3) 2.06 (1H, NH), 2.7-3.1 (10H, m, aromatic), 6.93 (2H, t, J=7H4 SCH2), 8.09.3 (15H, m, alkyl), m/e 472 (M+).

Example 6 2 - Anilino - 4 - phenyl - 5 - n - octylmercapto - 3 - aza - 1 - oxa - 6,6aSlV dithiapentalene To 5 - amino - 4 - phenyl - 1,2 - dithiole - 3 - thione (11.25 g) in dimethylformamide (25 ml) was added triethylamine (5.1 g). After stirring for ten minutes at room temperature phenyl isocyanate (6.0 g) was added and the solution stirred for a further thirty minutes. n - Octyl bromide (9.7 g) was added and the solution left to stand overnight. The precipitate was filtered off (yield 12 g, 54%) and recrystallised from ethanol as needles m.p. 103--1040C (Found: C, 63.1; H, 6.2; N, 5.9; S, 20.8, C24H28N2OS3 requires C, 63.2; H, 6.1; N, 6.1-S, 21.1%): t (CDCl3) 2.22 (1H, NH), 1.6-2.8 (10HV m, aromatic), 6.97 (2H, t, J=H2, S-CH2), 8.09.2 (15H, m, alkyl); m/e 456 (M+).

Example 7 2 - Anilino - 4 - carbomethoxy - 5 - n - octylmercapto - 3 - aza - I - oxa - 6,6aS'V dithiapentalene To 5 - amino - 4 - carbomethoxy - 1,2 - dithiole - 3 - thione (20.7g) in trimethylformamide (200 ml) was added triethylamine (10.1 g). After stirring for ten minutes at room temperature phenyl isocyanate (11.9 g) was added dropwise and the solution stirred for a further thirty minutes. n - Octyl bromide (19.3 g) was then added and the solution left to stand overnight. The precipitate (2.7 g, 61.5%) was filtered off and recrystallised from ethanol as needles m.p. 9798 (Found: C, 54.5; H, 6.3; N, 6.3; S, 21.8, C20H28N2O3S3 requires C, 54 8; H, 5.9; N, 6.4 S, 21.90/,); T (CDCl3) 1.77 (1H,NH), 2.3-3.1 (5H,m, aromatic), 6.10 (2H, S, CO2 Me), 6.92 (2H, t J27H SICH2), 8.0-9.3 (15H,m, alkyl); m/e 438 (M+).

Example 8 2 - Butylamino - 5 - methylmercapto - 4 - phenyl - 3 - aza - 1 - oxa - 6,6aSlV dithiapentalene To 5 - amino 4 - phenyl - 1,2 - dithiole - 3 - thione (11.25 g) in dimethylformamide (50 ml) was added triethylamine (5.2 g). After stirring for ten minutes at room temperature n - butyl - isocyanate (5.0 g) was added dropwise and the solution stirred for a further hour. Methyl iodide (7.3 g) was then added and the solution left to stand overnight. Water (500 ml) was added and the aqueous layer extracted with chloroform (3x 100 ml). The combined organic layers were washed with water (5x 100 ml) and dried over magnesium sulphate. Removal of the chloroform gave a red oil (17.0 g, 100%). This was chromatographed on a Florosil column to give the pentalene as a brown oil (Found: C, 53.0; H, 5.4; N, 7.5 C,5Hr8N2OS3 required, C, 53.3; H, 5.3; N, 8.3) m/e 338 (M+).

Example 9 2 - Heptylamino - 5 - methylmercapto - 4 - phenyl - 3 - aza - l,6,6aSlV - trithiapentalene To 5 - amino - 4 - phenyl - 1,2 - dithiole - 3 - thione (11.25 g) in dimethylformamide (50 ml) was added triethylamine (5.1 g). After stirring for ten minutes heptyl isothiocyanate (7.9 g) was added and the solution stirred at 500C for 6 hours. The solution was cooled to 300C and methyl iodide (7 g) added. Water (500 ml) was added and the aqueous solution extracted with ether (3x100 ml). The combined ether layes were washed with water (5 x 50 ml) and dried over magnesium sulphate. Removal of the ether gave an oily solid which was taken up in toluene, filtered and stripped to give a red oil (yield 7.2 g, 26%). This was chromatographed on florosil column to give the pentalene as a red oil (Found: C, 53.8%, H, 6.3%; N, 6.9%; S 32.1% C,8H24N2S4 requires C, 54.5; H, 6.1; N, 7.1; S, 32.3%).

Example 10 2 - Anilino - 5 - n.octylmercapto - 3,4 - diazo - I - oxa - 6,6aS'V - dithiapentalene To N - phenyl - N' - (3 - thione - 1,2,4 - dithiazyl - 5) - urea (Prepared as in Journal of Organic Chemistry 1970, 35, 1665) (26.9 g) in dimethylformamide (250 ml) was added octyl bromide (19.3 g). The solution was stirred for two hours at 800C and then cooled to 400C. Triethylamine (10.6 g) was added and the solution stirred for two hours at 400 C. The solution was cooled and the precipitate filtered off. It was recrystallised from chloroform to give the pentalene (28.6 g, 75%) as needles m.p. 174--1760C (Found: C, 53.7; H, 6.0; N, 10.9; S, 24.9; C,7H23N3OS3 requires C, 53.5; H, 6.0; N. 11.0; S, 25.2%), m/e 381 (M+) Example 11 5-Oleoamido-4-carbomethoxy-l,2-dithiole-3-thione: 5-AminoA-carbomethoxy- 1 ,2-dithiole-3-thione (20.7 g) was suspended in pyridine (100 ml) and oleoyl chloride (30.05 g) added dropwise with cooling in an ice bath. After the addition was complete the solution was stirred for two hours at 40". The solution was poured into water and extracted with chloroform (4x 100 ml).

The combined organic layers were washed with 2N hydrochloric acid (2x200 ml) and water (2x200 ml). After drying over magnesium sulphate the chloroform was removed to give a red oil which solidifed on standing (yield 48.0 g, 100%).

Recrystallisation from ethanol gave the amide as red crystals, m.p. 5455 .

(Found: C, 58.5; H, 7.8; N, 3.1; S, 20.3. C22H37NO3S3 requires C, 58.6; H, 7.8; N, 3.0; S, 20.4%), m/e 471 (M+) Example 12 4 - Carbomethoxy - 2 - heptadec - 8 - ene - 5 - methylmercapto - 3 - aza - 1 - oxa - 6,6aS'V - dithiapentalene 5 - Oleoamido - 4 - carbomethoxy - 1,2 - dithiole - 3 - thione (4.71 g) was added to a solution of sodium methoxide (0.54 g) in methanol (50 ml). Methyliodide (1.5 g) in methanol (10 ml) was added and the suspension stirred for 5 hours and then left to stand overnight. Water (500 ml) was added and the solution extracted with ether (3x 100 ml). The ester solution was washed with water (100 ml) and dried over magnesium sulphate. Removal of the ether gave an oil which was chromatographed on Florosil to give a red oil which crystallised on standing (Found: C, 59.7%; H, 8.1%; N, 2.8%; S, 19.6%. C24H39NO3S3 requires C, 59.4; H, 8.0; N, 2.9; S 19.8%); m/e 485 (M+) Example 15 In a series of tests the products prepared in Examples 2, 4, 5, 6, 7 and 8 were added to-oil and submitted to standard bench tests. Except for the 4 ball test the product was dissolved at a concentration of 0.5 wt % in a conventional 10 w/30 lubricating oil containing 6 wt % of conventional ashless dispersants. For the 4-ball test the concentration was 1 wt. %. To show the advantages of the azathiapentalenes of this invention two benzyl substituted thiapentalenes outside the scope of this invention were also tested and showed less favourable results.

The tests used were (ASTM D2272-67) (RBOT) in which the oil and oxygen are placed in a small pressure tank which is rotated and held at an elevated temperature and the oxidation stability is measured as the induction time before onset of oxidation. The oxidation stability was also measured by the modified catalysed oxidation (MOD/COT) test in which a sample of the oil containing 0.1% by weight of iron napthenate is stirred by a paddle made from a Petter (Registered Trade Mark) W-l engine bearing whilst blowing air at 710C through the oil for 48 hours. The degree of oxidation is shown by the percentage increase in the viscosity of the oil.

The effect of the oil in bearing corrosion was measured by a B earing Corrosion Rig (BCR) in which the oil is used in a rig consisting of a crankshaft rotating a Petter (Registered Trade Mark) W-l bearing for 36 hours at 1500C.

The anti-wear properties of the oils were measured by subjecting them to the 4 ball test and measuring the weld load in kilograms, and the scar diameter formed after 1 minute under a load of 120 kilograms.

The copper lead corrosion of the oils were also tested by attaching samples of copper and lead to a stirrer in a vessel containing the oil and blowing air through the sample for 20 hours at 3200F and then measuring the weight loss of the metal strips in milligrams. This is known at the SOD test AMS 290.91.

The test results were as follows: MOD/COT SOD BCR 4 Ball RBOT % visc. increase wt. loss mg wt. loss Weld load Compound (min) 30 hr. 48 hr. Cu PBb (mg) (kg) Wear Scar

C6Hs < C6HS 60 22400 oo 15 1830 39 220

C6N N N C5H 85 85 X oo m m 2 .14 11 390 s-s-s Ex 4 139 990 3820 4 3 19 250 2.05 Ex 7 188 3390 oo 33 128 120 280 2.00 Ex 5 180 2240 oo 6 3 21 270 1.85 Ex6 140 Co Co 8 60 11 230 2.10 Ex 8 94 660 oo 10 19 12 230 1.95 Ex 2 132 107 14000 16 3 132 310 1.85

Claims

WHAT WE CLAIM IS:1. Azathia pentalenes of the general formula:

where Y is

Z is O or S Q is -SR or -NHR4 when Z is S or R8 or -NHR4 when Z is O.

and R is hydrocarbyl and, R', R2 and R4 and R5 are the same or different and are hydrogen- and carbon-containing groups and R3 is hydrogen or a hydrogen- and carbon-containing group.
2. Azathiapentalenes according to Claim 1 in which R' and R3 are aromatic groups.
3. Azathiapentalenes according to Claim 1 or Claim 2 in which R, R2 and R5 are alkyl groups.
4. Azathiapentalenes according to Claim 3 in which R2 is methyl or ethyl.
5. Azathiapentalenes according to Claim 1 substantially as hereinbefore described with particular reference to the accompanying Examples.
6. A process for the production of compounds according to Claim 1 in which Q is -SR and Z is S comprising reacting a 5 - amino - 1,2 - dithiole - 3 - thione with carbon disulphide in the presence of a base followed by reaction with a halohydrocarbon.
7. A process for the production of compounds according to Claim I in which Q is -NHR4 and Z is S in which a 5 - amino - 1,2 - dithiole - 3 - thione is reacted with an isothiocyanate in the presence of a base followed by reaction with a halohydrocarbon.
8. A process for the production of compounds according to Claim 1 in which Q is -NHR4 and Z is 0 comprising reacting a 5 - amino - 1,2 - dithiole - 3 - thione with an isocyanate in the presence of a base followed by reaction with a halohydrocarbon.
9. A process for the production of compounds according to Claim 1 in which Q is-R8 and Z is 0 comprising reacting a 5 - amino - 1,2 - dithiole - 3 - thione with an acyl halide or acid anhydride and reacting the product with a halohydrocarbon.
10. A process for the preparation of compounds according to Claim I substantially as hereinbefore described with particular reference to Examples 1 to 10 and 12.
11. Azathiapentalenes whenever produced by a process according to any one of Claims 6 to 10.
12. Lubricating oil containing from 0.01 to 10 wt % of an azathiapentalene according to any one of Claims 1 to 5 and 11.