US3869395A

US3869395A - 2-amino-5-hydrocarbyldithio-1,3,4-thiadiazole and compositions thereof

Info

Publication number: US3869395A
Application number: US445384A
Authority: US
Inventors: James O Waldbillig
Original assignee: Texaco Inc
Current assignee: Texaco Inc
Priority date: 1974-02-25
Filing date: 1974-02-25
Publication date: 1975-03-04
Anticipated expiration: 1992-03-04
Also published as: US3940408A

Abstract

SEQUENTIALLY WITH AN ALKALI METAL HYDROXIDE AND A HYDROCARBYL SULFENYL BROMIDE CHARACTERIZED BY THE FORMULA R-S-Br where R and R'' are as heretofore defined. Hydrocarbon oil compositions comprising a hydrocarbon oil of lubricating viscosity containing between about 0.01 and 50 wt. percent of said amino hydrocarbyldithio thiadiazole.

WHERE R is hydrocarbyl of from 1 to 30 carbons and R'' is hydrogen or hydrocarbyl of from 1 to 30 carbons prepared by the method of contacting a 2-amino-5-mercapto-1,3,4-thiadiazole characterized by the formula:

Thiadiazole derivatives characterized by the formula:

Description

States Patent 1191 Waldbillig 1111 3,869,395 [451 Mar.4, 1975 2-AMINO-S-HYDROCARBYLDITHIO-l,3,4-

THIADIAZOLE AND COMPOSITIONS THEREOF [75] inventor: James O. Waldbillig, Wappingers Falls, NY.

[73] Assignee: Texaco Inc., New York, NY.

[22] Filed: Feb. 25, 1974 [21] Appl. No.: 445,384

Primary Examiner-W. Cannon Attorney, Agent, or Firm-T. H. Whaley; C. G. R165 [57] ABSTRACT Thiadiazole derivatives characterized by the formula:

where R is hydrocarbyl of from 1 to 30 carbons and R is hydrogen or hydrocarbyl of from 1 to 30 carbons prepared by the method of contacting a 2-amino-5- mercapto-l,3,4-thiadiazole characterized by the formula:

sequentially with an alkali metal hydroxide and a hydrocarbyl sulfenyl bromide characterized by the formula R-S-Br where R and R are as heretofore defined. Hydrocarbon oil compositions comprising a hydrocarbon oil of lubricating viscosity containing between about 0.01 and 50 wt. percent of said amino hydrocarbyldithio thiadiazole.

9 Claims, N0 Drawings 2-AMIljgkS-HYDROCARBYLDITHIO-1 ,3,4- THIADIAZOLE AND COMPOSITIONS THEREOF BACKGROUND OF INVENTION In the internal combustion engines of today as well as mechanisms associated therewith such an automatic transmissions, a substantial amount of copper is employed in the construction thereof. However, some of the most commonly used additives in lubricating oil compositions servicing the internal combustion systems, e.g., gear oils, are highly corrosive to copper. Specifically, among the most effective agents which have been developed for compounding with lubricants to improved extreme pressure and wear properties are sulfur containing organic compounds, for example, sulfurized triisobutylene and sulfurized diisobutylene, sulfurized terpene, sulfurized hydrocarbon oils, vegetable oils, animal oils, xanthate esters, organic polysulfides, particularly polyalkyl polysulfides which contain sulfur or sulfur compounds. These wear and extreme pressure agents are corrosive to copper. In addition, those hydrocarbon oils derived from high sulfur containing crude oils wherein the sulfurous components are not thoroughly removed in refining are often corrosive to copper.

To solve this problem of copper corrosion, the prior art employs various copper corrosion inhibitors with varying degree of effectiveness. One such class of inhibitors are disclosed in U.S. Pat. Nos. 2,719,125 and 2,719,126 which are directed to copper corrosion inhibited lubricating oil compositions containing as the copper coro s ion inhibitor a 1,3,4-thiadiazole polysulfide characterized by the formula:

E Ii -(S) Ps- SUMMARY OF INVENTION 1 have discovered and this constitutes one aspect of my invention a new class of sulfur compounds which are effective in inhibiting the corrosion of copper by copper corrosive hydrocarbon oil formulations. Another aspect of my invention are hydrocarbon oil formulations containing the novel sulfur compounds. More particularly, the instant invention relates to a 2- amino-S-hydrocarbyldithio-1,3,4-thiadiazole characterized by the formula:

NN R set Ii s-s-R where R is hydrocarbyl of from 1 to 30 carbons and R ishydrogen or hydrocarbyl of from 1 to 30 carbons. In

addition, the invention specifically relates to concotrate and finished hydrocarbon oil composition comprising a hydrocarbon oil of lubricating viscosity and said amino hydrocarbyldithio thiadiazole.

DETAILED DESCRIPTION OF THE INVENTION Specifically, the amino hydrocarbyldithio thiadiazole compounds of the invention are prepared by first reacting thiosemicarbazide of the formula:

where R is as heretofore defined. The reaction is carried out at a temperature between about 20 and 200C. utilizing a mole ratio of the thiosemicarbazide to carbon disulfide of between about 1:10 and 4:1. Further description of the 2-amino-5-mercapto-1,3,4- thiadiazole product can be found in US. Pat. No. 2,389,126.

The formed 2-amino-5-mercapto-l ,3;4-thiadiazole is then contacted with an alkali metal hydroxide such as sodium hydroxide and potassium hydroxide at a temperature between about 20 and 100C. utilizing a mole ratio of thiadiazole to alkali metal hydroxide of between about 2:1 and 1:1.1 to form the alkali metal mercaptide intermediate characterized by the formula:

l H S where M is the alkali metal moiety and R is as hereto fore defined.

The intermediate mercaptide salt is contacted with a hydrocarbyl sulfenyl bromide characterized by the formula R-S-Br where R is hydrocarbyl, i.e., alkyl, aryl, alkaryl or aralkyl of from 1 to 30 carbons. The reaction is conducted at a temperature between about 50 and 50C. utilizing a mole ratio of thiadiazole reactant to hydrocarbyl sulfenyl bromide of between about 1.1:! and 111.1. The sulfenyl bromide reactant is prepared by reacting hydrocarbyl mercaptan e.g. alkyl mercaptan with bromine at temperatures between about -50 and 50C. utilizing a mole ratio of mercaptan to bromine of between about 2:1 and 1:20.

In the foregoing described reactions, liquid diluents are advantageously employed, e.g., in amounts of between about 25 and wt. percent of the reaction mixtures. Examples of such diluents are benzene dimethylformamide, mixtures of benzene and dimethylformamide, toluene o, m-, and p-xylene and mixtures thereof, N,N-diethylformamide,' N,N- dimethylacetamide, diglyme (diethylene glycol dimethyl ether), chlorobenzene, carbon tetrachloride, hexachloroethane, ethylene glycol dimethyl ether. In

most instances a single solvent will not be suitable for all stages thus normally requiring the use of several different solvents.

All stages of the reaction are preferably conducted in an inert atmosphere such as nitrogen.

Examples of the thiosemicarbazide reactants contemplated herein are thiosemicarbazide, 4-ethyl-3- thiosemicarbazine, 4-propyl-3-thiosemicarbazide, 4-butyl-3-thiosemicarbazide, 4-pentyl-3- thiosemicarbazide, 4-heXyl-3-thiosemicarbazide, 4-heptyl-3-thiosemicarbazide, 4( Z-ethylhexyl )-3- thiosemicarbazide, 4-tert-octyl-3-thiosemicarbazide, 4-dodecyl-3-thiosemicarbazide, 4-tetradecyl-3- thiosemicarbazide, and 4-octadecyl-3- thiosemicarbazide, 4-methyl-3-thiosemicarbazide, 4-phenyl-3-thiosemicarbazide, 4-benzyl-3- thiosemicarbazide, 4-tolyl-3-thiosemicarbazide, 4-

naphtyl-3-thiosemicarbazide.

Examples of the amino mercapto thiadazoles contemplated herein are where R and Z are hydrogen where R is ethyl and Z is hydrogen; where R is hydrogen and Z is potassium; where R is ethyl and Z is potassium; where R is hydrogen and Z is sodium, where R is methyl and Z is potassium; where R is tert-octyl and Z is potassium; where R is dodecyl and Z is sodium; where R is octadecyl and Z is sodium; where R is tolyl and Z is potassium; where R is phenyl and Z is sodium; where R is naphthyl and Z is potassium and where R is benzyl and Z is sodium.

Examples of the hydrocarbyl sulfenyl reactants are -t-dodecyl sulfenyl bromide, t-octyl sulfenyl bromide,

Z-methyl-Z-butyl sulfenyl bromide, 3-methyl-l-butyl sulfenyl bromide, n-pentyl sulfenyl bromide, n-octyl sulfenyl bromide, n-dodecyl sulfenyl bromide, noctadecyl sulfenyl bromide, tolyl sulfenyl bromide, naphthyl sulfenyl bromide, phenyl sulfenyl bromide and benzyl sulfenyl bromide.

Examples of the amino hydrocarbyldithio thiadiazole products contemplated herein are 2-amino-5-tdodecyldithiol ,3,4-thiadiazole; Z-ethylamino-S-toctyldithio-l ,3,4- thiadiazole; 2-amino-5-t-octyldithio- 1,3,4-thiadiazole; 2amino-5-n-octadecyldithio-l ,3,4- thiadiazole; Z-ethylamino-S-n-octadecyldithio-l,3,4- thiadiazole; 2-(2-ethylhexyl)amino-5-n-dodecyldithio- 1,3,4-thiadiazole; 2-( 2-ethylhexyl)amino-5-noctyldithio-l ,3,4-thiadiazole; 2naphthyl-5-octyldithio- 1,2,3-thiadiazole; 2-benzyl-5-pentyldithio-l ,3 ,4- thiadiazole; 2-amino-5-phenyldithio-l,3,4-thiadiazole and 2-amino-5-tolyldithio-1,3,4-thiadiazole.

In regard to the finished compositions of the present invention, the amino hydrocarbyldithio thiadiazole products are employed in hydrocarbon base oil in copper corrosion inhibiting amounts, e.g., from between about 0.01 and wt. percent, preferably between about 0.05 and 1 wt. percent. The hydrocarbon base oil in the finished composition normally constitutes at least about 85 wt. percent of said composition, preferably about 90 wt. percent or more. Hereinbefore and hereinafter by the term finished" it is intended to denote that the composition is in a state ready for ultimate use without need for further dilution with base oil.

In the concentrate compositions contemplated to which additional hydrocarbon oil is added to form the finished compositions, the concentrate form bcing preferably for storage and transport, the hydrocarbon base oil normally constitutes at least about 50 wt. percent, preferably between about 50 and wt. percent and the amino hydrocarbyldithio thiadiazole between about 10 and 50 wt. percent of the concentrate formulation.

Thus, concentrate and finished compositions are contemplated ranging from at least about 50 wt. percent hydrocarbon oil and between about 0.01 and 50 wt. percent amino hydrocarbyldithio thadiazole additive.

The hydrocarbon oil components employed in the finished and concentrate formulations of the invention advantageously are mineral lubricating oils such as paraffinic lube oil, naphthenic lube oil and mixtures thereof. Other suitable hydrocarbon oils are those synthetically formed such as the polyalkylene, e.g., polyisobutylene of a molecular weight of from about 1,000 to 5,000. The viscosity of the base oils employed will be dependent upon the particular use intended for the finished formulation. However, the viscosity of oil employed will generally range between about 70 and 5,000 SUS at F.

In addition to the hydrocarbon oil and amino hydrocarbyldithio thiadiazole components in the contemplated oil compositions, other additives are normally employed, the particular other additives utilized being dependent on the specific service intended for the finished compositions of the invention. Some of the other additives contemplated belong in classes of detergentdispersants, pour depressants, VI improvers, extreme pressure agents, antiwear agents, antioxidants, supplementary corrosion inhibitors and antifoamants.

Examples of the extreme pressure and antiwear agents are dithiolethione derived from sulfuriziing triisobutylene and alkyl sulfides, disulfides and polysulfides prepared by sulfurization of isobutylene with sulfur dichloride. Other extreme pressure and antiwear agents contemplated are the sulfurized terpenes, sulfurized hydrocarbon oils and polyalkyl polysulfldes, all of which contain active sulfur or sulfur compounds which are corrosive to copper. These extreme pressure and antiwear agents are normally present in the finished formulations (when utilized) in amounts of between about 0.1 and 10 wt. percent, preferably between 0.5 and 5 wt. percent.

When detergent-dispersants are employed, they are usually utilized in amounts between about 0.5 and 5 wt. percent. Examples of ashless dispersants are alkenyl succinimides characterized by the general formula:

ene, tetramine, tetraethylene pentamine derivatives of polyisobutylene succinic anhydride, particularly where R is of a molecular weight between about 700 and 2,000, e.g., about 1,300. These ashless dispersants are further described in U.S. Pat. Nos. 3,172,892 and 3,202,678. The non ashless dispersants which may be utilized are the alkaline earth metal overbased calcium alkaryl sulfonates such as calcium carbonate overbased calcium alkaryl sulfonate wherein the alkaryl sulfonate moiety is of a molecular weight of 500 to 1,000. These overbased sulfonates are further described in U.S. Pat. Nos. 3,027,325, 3,312,618 and 3,537,996.

Examples of the contemplated viscosity index improvers which in many instances also function as pour depressors are the methacrylate ester polymers characterized by the general formula:

where R is an alkyl group, a dimethylamino group or mixtures of said group containing from 1 to 20 carbons and y is an integer providing a molecular weight of the polymer in the range of 25,000 to1,250,000, preferably 50,000 to 500,000. Methacrylate ester polymers possessing pour point depressant as well as viscosity index improving properties are well known, e.g., U.S. Pat. No. 2,737,496. A very effective material of this type is the tetrapolymer of butyl, lauryl, stearyl and dimethylaminoethyl methacrylate in approximate ratios of 1:2:1:0.2. The methacrylate ester is advantageously employed in the base oils in amounts ranging from 0.1 to wt. percent, preferably about 0.2 to 5 wt. percent, in order to impart the desired viscosity index and/or pour point thereto.

Examples of suitable antioxidants which also function as supplementary corrosion inhibitors are the aryl substituted amine compounds exemplified by phenylnaphthylamine as well as compounds such as phenylenediamine, phenathiazine, diphenylamines employed in amounts between about 0.1 and 5 wt. percent. Some of the preferred compounds are the phenylalphanaphthylamines and a mixture of 2,2-diethyl-4,4'- t-dioctyldiphenyleneamine and 2,2'-diethyl-4,6- diphenylamine.

Additional examples of antioxidants are the hydrocarbyl dithiophosphates. Particularly effective compound in this class are zinc di(nonylphenoxyethyl) dithiophosphate, zinc di(dodecylphenoxyethyl) dithiophosphate and zinc di(nonylphenoxyethoxyethyl) dithiophosphate prepared by reacting nonyl phenol and ethylene oxide compounds with phosphorus pentasultide followed by neutralization of the acid formed with basic zinc compound such as zinc carbonate, zinc oxide or zinc hydroxide. The general preparation and description of the compounds in this class are disclosed in U.S. Pat. Nos. 2,344,395 and 3,293,181.

Examples of additional supplemental corrosion inhibitors are oleyl amine and ethyloleyl acid phosphate.

Antifoamants which are suitable for use are the sililcone polymers such as polymeric dimethyl silicone.

The following examples further illustrate the invention but are not to be construed as limitations thereof.

EXAMPLE I This example illustrates the preparation of -2-amino- S-mercapto-l ,3,4-thiadiazole reactant.

To a solution of 45.5 grams (0.5 mole) of thiosemicarbazide in 1,000 mls. of dimethylformamide there was charged 32 grams of carbon disulfide. The resultant solution was heated for 4 hours at C. and then stripped to 93C. under reduced pressure of 0.15 mm Hg. The residue was slurried. with 250 mls. of benzene followed by removal of the benzene via distillation. The residue product was recrystallized from 250 mls. of methanol-ethanol mixture (Formula 30) to yield 28 grams (42 wt. percent) of product which was analyzed and found to be 2-amino-5-mercapto-l,3,4- thiadiazole having an elemental analysis of 31.7 (calc. 31.6) wt. percent nitrogen; 47.1 (48.1) wt. percent sulfur; 19.2 (18.0) wt. percent carbon and 2.1 (2.3) wt. percent hydrogen.

EXAMPLE ill This example illustrates the preparation of 2- ethylamino-5-mercapto-l ,3,4-thiadiazole reactant.

To a stirred solution of 11.9 grams (0.10 mole) of 4-ethyl-3-thiosemicarbazide and 700 mls. of dimethylformamide there were charged 8.4 grams (0.1 l of carbon disulfide. The reaction mixture was heated at C. for 4 hours and stripped to 93C. under reduced pressure of 0.04 mm Hg. The residual solid was recrystallized from absolute ethanol and analysis found it to be 2-ethylamino-5-mercapto-1,3,4-tlhiadiazole of an elemental analysis of 29.5 (calc. 29.8) wt. percent carbon; 4.7 (4.4) wt. percent hydrogen; 2.5.6 (26.1) wt. percent nitrogen and 39.4 (39.7) wt. percent sulfur.

EXAMPLE III This example illustrates the preparation of a species of the product of the invention from a product of the type formed in Example I.

A solution of 5.6 grams (0.] mole) of potassium hydroxide and 50 mls. of ethanol was added to a mixture of 13.3 grams (0.10mole) of 2-amino-5-mercapto- 1,3,4-thiadiazole in 200 mls. of diglyme (diethylene glycol dimethyl ether) at 0C. There was added mls. of benzene and the resultant mixture was heated to 49C. on the rotary evaporator to remove benezene and ethanol leaving the potassium salt of 2-amino-5- mercapto-1,3,4-thiadiazole as residue.

A t dodecyl sulfenyl bromide solution was prepared by adding 16 grams (0.10 mole) of bromine to a solution of 100 mls. of carbon tetrachloride and 20.2 grams (0.10 mole) t-dodecyl mercaptan at a temperature of about 0C. The product was blown with nitrogen for a period of 2 hours.

The formed t-dodecyl sulfenyl bromide solution was added to the above formed potassium salt. The resultant product was stripped to 93C. (0.15 mm Hg), dissolved in 300 mls. of ether, and filtered through paper. The filtrate was washed twice with 300 mls. of 5 wt. percent aqueous sodium carbonate and the resultant solution was dried over sodium sulfate and stripped to 93C. under a reduced pressure of 0.125 mm Hg. The residual solid weighed 19 grams representing a yield of 57 wt. percent. Analysis found it to be a 2-amino-5-6- dodecyldithio-1,3,4-thiadiazole having an elemental analysis of 9.7 (calc. 12.6) wt. percent nitrogen 26.2

EXAMPLE IV This example illustrates the preparation of still another species of the product of the invention.

A solution of0.56 gram (0.01 mole) of potassium hydroxide in 25 mls. of anhydrous ethanol was added to Z-(ethylamino)-5-mercapto-l,3,4-thiadiazole in 100 mls. of diethylene glycol dimethyl ether at C. under a nitrogen blanket. To the resultant mixture 15 mls. of benzene was added and the mixture was heated at 49C. on a rotary evaporator to remove ethanol, benzene and water leaving residual solution of potassium salt of 2-(ethylamino)-5-mercapto-1,3,4-thiadiazole.

A t-octyl sulfenyl bromide-carbon tetrachloride solution was prepared by adding 1.76 grams (0.11 mole) bromine to a solution of 1.61 grams (0.1 1 mole) t-octyl mercaptan and 50 mls. carbon tetrachloride solution at 10 dropwise. The resultant mixture was stirred with nitrogen blowing for two hours at about 0C.

The t-octyl sulfenyl bromide solution was added to the aforeformed residual solution at 0C. The resultant product was filtered and stripped to 93C. (0.1 mm Hg). The product was then dissolved in 150 mls. of ether and washed twice with two 150 ml. portions of 5 wt. percent aqueous sodium carbonate and then dried over sodium sulfate. The dried product was stripped to 93C. (0.1 mm Hg.) leaving a solid residue of 2.3 grams which upon analysis was identified as 2-ethylamino-5-toctyldithio-l ,3,4-thiadiazole having an elemental analysis of 48 (calc. 47.2) wt. percent carbon, 7.7 (7.5) wt. percent hydrogen, 1 1.4 (13.8) wt. percent nitrogen and 28.2 (31.5) wt. percent sulfur.

EXAMPLE V This example further illustrates the preparation of still another species of the product of the invention.

A solution of 28.05 (0.5 )grams of potassium hydroxide in 200 mls. of ethanol was combined with 60 grams (0.45 mole) of 2-amino-5-mercapto-l,3,4-thiadiazole in 500 mls. of diethylene glycol dimethyl other at 0C. There was then added 200 mls. of benzene and the mixture was then stripped to 92C. on a rotary evaporator removing 310 mls. of solvent leaving as residue the potassium salt of 2-amino-5-mercapto-l,3,4-thiadiazole.

A t-octyl sulfenyl bromide solution prepared by adding 80 grams (0.5 mole) bromine to 73 grams (0.50 mole) t-octyl mercaptan in 500 mls. carbon tetrachloride while blowing with nitrogen at about 0C. followed by passage of nitrogen through the solution vigorously for 2 hours was added at C. to the potassium salt residue. The resultant mixture was stirred at ambient temperature for 1 hour and then filtered. The solids were washed with ether and the combined organic phase was stripped to 93C. on a rotary evaporator. There was recovered as residue 91.5 grams of a solidliquid mixture. The product was dissolved in 500 mls. of ether and washed with two 500 ml. portions of 5 wt. percent aqueous sodium carbonate. The washed product was dried over magnesium sulfate. Additional solids formed. The solids were removed and 200 mls. of pentane were added to the solution. The resultant solution was filtered and stripped to 93C. (rotary evaporator) and the resultant product was solid. Analysis determined it to be 2-amino-5-t-octyldithio-1,3,4- thiadiazole having an elemental analysis of 14.8 (15.2)

wt. percent nitrogen and 34.4 (34.6) wt. percent sulfur.

EXAMPLE VI This example illustrates the lubricating oil compositions containing the amino hydrocarbyldithio thiadiazole product and the effectiveness of the amino hydrocarbyldithio thiadiazoles as copper corrosion inhibitors in said compositions.

The following is a description of the base oil formula tions to which the amino hydrocarbyldithio thiadiazole products prepared in the preceding examples are added in varying amounts and to which comparative inhibitor components are added. The resultant formulations are subjected to the ASTM Copper Strip Corrosion Test (D 130-56). Briefly, this test Comprises placing a polished copper strip in the test oil composition for a 3 hour period at 250F. whereupon the degree of corrosive attack upon the strip is measured using a rating ranging from 1A to 4C with the rating of 1A representing the least corrosive attack and the rating of 4C representing the greatest corrosive attack.

In following Table l is a description of the base oil formulations:

TABLE 1 Base Oil Base Oil Ingredients A Paraffinic (1000 SUS at F.) 93.1 92.5 Ethyloleyl Acid Phosphate 1.0 1 Sodium Sulfide Treated Diiso- 5.0

butylene Polysulfide* Sulfurized Triisobutylene* 5 Terpolymer of but 1, lauryl, 0.2 0.5

stearyl and dimetiiylaminoethyl methacrylates Mixture of 2-mercaptobenzothia- 0.5

zole and t-C -C alkylamine Oleylamine 0.2 l Dimethyl Silicone Antifoamant 100 ppm *Extremc pressure agent corrosive to copper.

Table 11 below contains a description of the representative formulations of the invention and comparative formulations. Further, the formulations are compared basis the ASTM Copper Strip Corrosion Test as to their relative corrosiveness to copper, that is, the relative effectiveness of the copper corrosion inhibiting representative and comparative corrosion inhibiting additives in the hydrocarbon oil formulations.

Commercial lnhibitor.

In the above Table II a comparison of the copper strip ratings of representative Runs 1, 2, 6, 7 and 8 with control Runs and demonstrate the effectiveness of the amino(hydrocarbyldithio)-thiadiazole products of the invention in inhibiting corrosion. Further, a comparison of representative Run Nos. 1, 2, 6, 7 and 8 with comparative Run Nos. 3 and 9 demonstrate that the thiadiazole products of the invention have an effectiveness of essentially the same quality as a widely used commercial corrosion inhibitor.

1 claim:

1. A composition comprising a major amount ofa hydrocarbon oil of lubricating viscosity and between about 0.01 and 50 wt. percent of an amino hydrocarbyldithio thiadiazole characterized by the formula:

NN RITI- (HJSSR where R is alkyl, aryl, alkaryl or aralkyl of from 1 to carbons and R is hydrogen or alkyl, aryl, alkaryl or aralkyl of from 1 to 30 carbons.

2. A composition in accordance with claim 1 wherein said amino hydrocarbyldithio thiadiazole product is present in an amount of between about 0.01 and 10 wt. percent.

3. A composition in accordance with claim 1 wherein said thiadiazole product is present in an amount of between about 10 and 50 wt. percent.

4. A composition in accordance with claim 2 wherein R is t-dodecyl and R is hydrogen.

5. A composition in accordance with claim 2 wherein R is t-octyl and R is hydrogen.

6. A composition in accordance with claim 2 wherein R is t-octyl and R is ethyl.

7. A composition in accordance with claim 3 wherein R is t-dodecyl and R is hydrogen.

8. A composition in accordance with claim 3 wherein R is t-octyl and R is hydrogen.

9. A composition in accordance with claim 3 wherein R is t-octyl and R is ethyl.

Claims

1. A COMPOSITION COMPRISING A MAJOR AMOUNT OF A HYDROCARBON OIL OF LUBRICATING VISCOSITY AND BETWEEN ABOUT 0.01 AND 50 WT. PERCENT OF AN AMINO HYDROCARBYLDITHIO THIADIAZOLE CHARACTERIZED BY THE FORMULA:

4. A composition in accordance with claim 2 wherein R is t-dodecyl and R'' is hydrogen.

5. A composition in accordance with claim 2 wherein R is t-octyl and R'' is hydrogen.

6. A composition in accordance with claim 2 wherein R is t-octyl and R'' is ethyl.

7. A composition in accordance with claim 3 wherein R is t-dodecyl and R'' is hydrogen.

8. A composition in accordance with claim 3 wherein R is t-octyl and R'' is hydrogen.

9. A composition in accordance with claim 3 wherein R is t-octyl and R'' is ethyl.