DE2238302A1 - DIBENZIMIDAZOLE COMPOUNDS, METHOD FOR THEIR MANUFACTURE AND THEIR USE - Google Patents

Description

Shell Internationale Research Maatschappij N.V. The Hague, Netherlands

Dibenzimidazole compounds, processes for their preparation and their use

Priority: August 5, 1971, USA No. I69 459 August 5, 1971 USA No. I69 460

The invention relates to dibenzimidazole compounds. Further concerns the invention processes for their preparation and the use of these compounds as thickeners for lubricating greases.

Lubricating greases used for high temperature lubrication at temperatures from 175 to 235 ° C, for example, are becoming increasingly important.

It has been found that grease blends' with excellent High-temperature lubricating properties can be produced by adding a

adds a small amount of a dibehzimidazole compound ". ¹

309807/1339

The invention accordingly relates to dibenzimidazole compounds below Formula:

R ₁ -NCN

in the R ₁ and R _? Hydrocarbon residues with 6 to 30 carbon

atoms are or 0 H

Il I
R ₆ -XCNR ₄ - and R ₇ -XCNR ₅ radicals

0 H Il l

mean, in which R, - and R "aliphatic ^ hydrocarbon-

matic residues with 6 to 30 carbon atoms, R ₂ , and Rp-divalent sro / hydrocarbon residues with 6 to 20 carbon atoms, X is an oxygen atom or the imino group

. ". · Is and in. The R _{7 is} a divalent hydrocarbon radical having 2 to 20 carbon atoms.

The lubricating grease mixtures according to the invention have high dropping points, excellent mechanical and thermal stability and excellent bearing lubrication properties "

at high temperatures. These excellent properties obviously go in large part on the particular dibenzimidazole structure of the present thickeners back, which leads to an extremely stable molecule.

Dibenzimidazole compounds whose Rr and Ra residues are hydrocarbon residues with 6 to 30 carbon atoms can

309807/1339

BATH ORIGINAL

smoothly by reacting one mole of a dicarboxylic acid HOOC-R ₃ -COOH or its anhydride with 2 moles of a nitro-substituted phenylenediamine, subsequent. Reduction of the nitro groups to amino groups, for example ₄ with hydrogen, and further reaction with 2 mol of a monoisocyanate R «., P% -NCO can be prepared.

Dibenzimidazole compounds with R ₁ and R _o radicals, the

X d. 1

RjT, Rg ", " Rr and R "radicals can be easily obtained by reacting one mole of the aforementioned dicarboxylic acid or its anhydride with two moles of the nitro-substituted phenylenediamine described, subsequent reduction of the nitro groups, amino groups and further reaction with two moles of the reaction product aromatic diisocyanate OCN-Rj ,, ~ ·, -NCO with a monohydric alcohol R ^, "v-OH or a monoamine R ^ ," \ -NH ₀ her-

6 (7) o (7) 2

be asked.

It can also be a phenylenediamine without nitro groups

used, and the product obtained then to bis-nitrobenzimidazole are nitrated, which then becomes the amino compound reduced and with two moles of the monoisocyanate or diisocyanate reaction product is implemented »

Suitable dicarboxylic acids and their anhydrides are. ^ aliphatic dicarboxylic acids such as succinic acid, glutaric acid _{9 s} adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid, as well as aromatic dicarboxylic acids such as phthalic acid ,, _s isophthalic acid

309807/1339

and terephthalic acid or its anhydrides or esters. Cycloaliphatic acids such as cyclohexanedicarboxylic acids, e.g. 1,2- or 1,1-cyclohexanedicarboxylic acid and e.g. tetrahydrophthalic acid are also suitable. Hydrocarbon-substituted Dicarboxylic acids and their anhydrides can also be used, e.g., alkyl or alkenyl substituted succinic anhydrides the formula

R-OH -C.

in which R is an alkyl or alkenyl substituent with 1 to 16 or is more carbon atoms. Aliphatic dicarboxylic acids or their anhydrides with such a carbon number used, the remainder of which is R-, generally 2 to 20, preferably Contains 2 to 12 and especially 2 carbon atoms.

Phenylenediamines which are preferably used contain the amino groups in ortho division. A suitable diamine is 4-nitro-o-phenylenediamine. In addition to the nitro substituent, other substituents such as alkyl or halogen substituents may be present, but with the proviso that they the reaction of the phenylenediamine with the dicarboxylic acid or its anhydride do not significantly interfere. Diamines not yet substituted with the nitro group are iJ-chloro-o-phenylenediamine and 3, ^ - toluene diamine.

Suitable monoisocyanates are aliphatic or aromatic

OfHGtNAL INSPECTED

03T0312W JM * ß «* ° 3 0 9 8 0 7/1339

Monoisocyanates, which preferably have at least one aliphatic .Substituenten. Preferred monoisocyanates are straight or branched, saturated or unsaturated aliphatic monoisocyanates with 6 to 30 and in particular 12 to 24 carbon atoms ImR ₁ Z ₂ X-ReSt, such as cyclohexyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, Octadecyl, eicosyl and docosyl isoeyanates and their mixtures. In particular, aliphatic isocyanates with 16 to 18 carbon atoms in the R ^ fpx "radical are used.

Suitable aromatic diisocyanates are mono- or binuclear aromatic diisocyanates such as biphenylene, naphthylene, mono-, phenylene and tolylene diisocyanates, as well as 3,3-dimethylbiphenyl-4,4'-diisocyanate, Diphenylmethane-4,4'-diisocyanate and 2,4-ethylene diisocyanate. "In particular are 2,4-iolylene diisocyanate" and mixtures from 2,4- and 2,6-tolylene diisocyanates suitable.

Suitable monohydric alcohols are aliphatic alcohols with 6 to 30, preferably 12 to 24 and in particular 16 to 18 Carbon atoms, stearyl or oleyl alcohol or their mixtures are particularly preferred »

Suitable monoamines are aliphatic monoamines or those with preferably aliphatic character with 6 to 30, preferably 12 to 24 and especially 16 to 18 carbon atoms.

Mixtures of these alcohols and mixtures of these amines can also used "~

3 09807/1339 OnnstHAi

will.

The compounds according to the invention are used in lubricating grease mixtures generally used in an amount sufficient to thicken the oily carrier liquid to a fat consistency. This may require undifferentiated amounts, e.g. of

mean

about 5 to 50 percent by weight, based on the total mixture. In the all-rich however, thickener concentrations of 10 to 35 percent by weight in order to give the mixture to be produced the desired consistency granted.

A variety of lubricating oils can serve as the carrier fluid for the present blends. Suitable base oils are Mineral lubricating oils based on naphthenes, paraffins, etc. their mixtures with a viscosity of 50 SIIS at 37.8 ° C to 300 SUS at 98.9 ° C, synthetic

Hydrocarbon oils, such as oligomerized oC ~ 0iefine and oils derived from coal products. Synthetic oils such as alkylene polymers, alkylene oxide polymers, Polyalkenglycole, polyether, organophosphate, dicarboxylic acid ester and pentaerythritol ester ■: ■ are also suitable. The above oils can be used either individually or, if they are miscible or can be made miscible by solvents, as mixtures. Of the above base oils, mineral lubricating oils having viscosities of about 400 to 700 SUS at 37.8 ° C are particularly preferred.

309807/1339 ^^ _{| NsrecTE} o

The greases present can also contain additives such as corrosion inhibitors, for example disodium sebsoinafc, glycerol monooleate, sodium sulfonates, sodium nitrite, amino and benzotriazoles and isostearamides or imidazolines of tetraethylene pentamine ₉ ⁴ Oxidation inhibitors such as phenyl-a-naphthylamine, phenyl-a-naphthylamine, phenyl-a-naphthi-amine, phenylthyl-ß-naphthylamine, phenylthyl-ß-naphthylamine, phenylthyl-ß-naphthylamine, phenylthyl amine contain numerous analogues and homologues of these compounds, viscosity index improvers, such as methacrylate polymers υχιύ -mfecl ^ J ^ nerisateiH.öÄisMnjckaädili've vsnä other additives known for certain purposes.

The examples explain the invention

example 1

3'02 g · (2 * 'mol) Vnitro-o-tHeriyleridiamiri / ΪΟΟ' g '(l'"Möl5"'Bei'nstein-'" ^: - acid anhydride and 2 liters of 4 η hydrochloric acid are stirred for 2Λ hours The reaction mixture is cooled to 0 ° C. and filtered. The filtrate is veritforfen »The precipitate is neutralized with ammonia, ₉ filtered off again, washed twice with water and then dissolved under reflux in ethylene glycol, treated with activated charcoal, ., filtered and the filtrate was cooled, the precipitate that crystallized out is filtered off, washed with ethanol and dried _o yield: 65 g l, 2-bis- (5 ~ Nitrobenzimidazoyl-2) ethane, melting point 305 ⁰ C ₀

56 g (0 ₅ 16 mol) of this compound are added in 1200 ml of 3 η hydrochloric acid, the palladium on a carbon catalyst

« _Noon H, _n , _fl ORIGINAL INSPECTED

309807/1339

is, suspended and the reduction of the nitro groups in one Low pressure hydrogenation carried out. The catalyst is then filtered off and the filtrate is neutralized with sodium bicarbonate

,. and

and the precipitate obtained is filtered off. After wsrdiai with water /

Drying gives 4l, 5 gl, 2-bis (5-aminobenzimidazoyl-2) ethane with a melting point of 15 ¹ * to 155 ° C.

A 500 ml capacity equipped with a mechanical stirrer Plastic bottle is filled with 14.6 g (0.05 mole) of the above Compound together with 30 g (0.1 mol) of a mixture charged from octadecyl isocyanate and hexadecyl isocyanate in a molar ratio of 70:30 in 253 g of a neutral HVI-500 oil This suspension is stirred in a. Nitrogenous atmosphere heated to 127 ° C. After the reaction is finished, the content cooled to about 110 ° C and then ground. The fat obtained has an ASTM dropping point of 265> 6 ° C. and an ASTM water penetration of 272 at '60 impacts.

Example2

A series of dibenzimidazole diurea thickeners according to the invention containing grease mixtures are used various carrier oils. The substances used to produce the thickeners in question and the Properties of the grease mixtures thickened with them are given in Table I:

ORIGlNALiNSPECTED 309807/1339

Grease mixture

Reactants
"SdrtT Ph ^ rl-di-i.

table I.

Isocyanate base thickener oil concentration, weight -Ά

ASTM penetration

not τ, ^ ■ μ *. fulled tumbled ^ö

(0 bumps) (60 bumps)

Succinic acid-4-nitro-anhydride phenylenediamine

7o mole percent

^C 18 ^H 37 ^NC P

30 mole percent 15

250

272

265.6

(O
OO
O

Succinic anhydride

Succinic anhydride

Berns teinsäuraanh / drid

Adipic acid

4-nitro-o-

phenylene

diamine

70 mole percent 18

238

283

267.2

30 mole percent ^C 16 ^H 33 ^NCO

4-nitro-o-. 100 mole percent phenylenediamine

^C 18 ^H 37 ^NGO

4-nitro-o-

phenylene

diamine

4-nitro-o-

phenylene

diamine

100 mole percent

70 mole percent, 30 mole percent

Succinic acid-4-nitro-anhydride phenylenediamine

63 mole percent

27 mole percent

10 mole percent C ₁₇ H ₃₃ NCO

14th

11

15th

14th

290

260

275

279

250

298

279

253

267.8

261.1

co oo co

Table I (continued)

Reactants

Grease mixture

Acid or anhydride

Phenylenediamine isocyanate

Base thickness center oil concentration, wt. -Z

ASTM penetration

not

fulled

(0 bumps) (60 bumps)

fulled

ASTM drop point
° C

Succinic acid-4-nitro-anhydride phenylenediamine

Succinic acid-4-nitro-anhydride phenylenediamine

70 mole percent D.

30 mole percent

70 mole percent EC ₁₈ H ₃ -NCO

30 mole percent

10

234

285

15th

253

234

Succinic acid 9 anhydride

4-nitro-o-

phenylene

diamid

100 mole percent C

15th

257

290

Base oil A - mineral lubricating oil having a viscosity of 500 Sayholdt universal seconds at -37.8 ⁰ C base oil B - mineral lubricating oil having a viscosity of 70 Saybolt universal seconds at -98.9 ° C

Base oil C - Synthetic hydrocarbon oil from orögomerisierten a-01efinen having a viscosity of 51.4 seconds Universal Saybolt bei.-98.9 ^o C

Base oil D - mineral lubricating oil having a viscosity of 430 Saybolt Universal Seconds at 37.8 ⁰ C base oil E - mixture of HexodeCylisostearat. and esters of dimeric acids

OO CjJ CD K)

Example3

To demonstrate the excellent high temperature performance _s some conventional oxidation and corrosion inhibitors containing greases from Example 2 are "described and" the "Navy High Speed Bearing Test ^1} as in" Federal Test Method 331.1 Pope Bearing Test ", as in" Federal Test Method Standard 791a, Method 333 "described> subject. Based on this. ':'! Test method, the service life of the Lagep is expressed in hours and represents the time until the bearing fails. The test results are given in the table below.

Table II

Test ■ 'grease ^; Grease. '

Mixture 1 Mixture 6

Navy High Speed Bearing

Test 148.9 C, 10,000 rpm,

Lifetime of the L-xger, ₀ \

Hr · · "3.388 * '4.871

Pope Bearing Test, 176.7 ° C

Life of the bearing, ₉ \

Hours . ■ 405 ^;

1 ")
'Contains 1 wt .- # phenyl-a-naphthylamine, 0.5 wt -.% Oronit (Dilaurylselenid), 1 wt -.% Natriumsebtcinsfc and 0.4 part by weight JS 3-amino-l, 2,4-triazole .

O\ ■ ·

^; Funds from two exams.

ORIGINAL WSPEOTED 309807/133 9

Example 4

Other dibenzimidazole thickeners and greases of the invention are shown in the table below.

Table III

Acid or
anhydride Reactants Monoisocyanate Base-
Oil ¹ ^ Grease
mix 1,2-cyclohexane
dicarboxylic acid
anhydride Phenylene
diamine 70 mole percent
30 mole percent A. 10 Azelaic acid iJ-Nitro-o-
phenylene
diamine 70 mole percent
30 'mole percent A '*' '11 Succinic acid
anhydride 4-nitro-o-
phenylene
diaminv '■ ·· ■ 100 mole percent
C ₂₂ H ₁₁₅ NCO B. 12th Phthalic acid
anhydride 4-nitro-o-
phenylene
diamine 75 mole percent
25 mole percent
C ₁₆ H ₃₃ HCO E. 13th 3-nitro-o-
phenylene
diamine

See footnote in Table I.

Example 5

In the course of the production and testing of various lubricating greases containing the thickeners according to the invention, it was

, .- ν ,,: ^, v: -via 309807/1339 original

found that the dibenzimidazole diurea according to the invention compounds when taken with alkylphenol or arylamine antioxidants and iasbssmdere with di- or trialkylphenols and Phenylnaphthylamines used are a notable one. have acidation-inhibiting activity. This beneficial effect is evidenced by the results given in Table IV using an air oxidation test carried out at 176.7 ° C from samples of the mineral base oils containing the indicated concentrations of antioxidants and thick oils are. In this test, 9 liters of air per hour are passed through 100 g of the test sample, which is 0.002 percent by weight soluble Iron has been added. The outflowing air is released after • .removing the impurities with an oxygen analyzer which measures the oxygen content of the air. Under use." '"a- Vergieichsluitstrom'will" die Geschwiridigk-ei't "der Sauer-"' ■ ·· · Substance uptake calculated. The test result, referred to as the "induction period", is defined as that for absorption time required by one millimole of oxygen through the sample. The sample has a temperature of 176.7 ° C in this test.

ι ₄

Table IV

Grease- Alkylphenol- ^ Arylamin- ₂ y Dibenzimidazgl- Luftoxidagemisch Antioxidant 'Antioxidant Diurea tion test

Wt .-% wt .-% "induction period '· hrs.

A 1.5 1.5 - ²¹

B - - 1.0 2

C 1.5 x 1.5 L, o 72.86

^, ö-di-tert.-butyl-iJ-methylphenol ^ thickener of the Schmjler-

2) fat mixture 1

octylated phenyl-a-naphthylamine

8 0 7/1339 OfifiSINAt iWSPECTED

Example 6

270 g (1 mol) of stearyl alcohol are added to a solution of 2 liters of chloroform and 522 g (3 mol) of technical 2,4-tolylene diisocyanate Stirred in over 2 hours. The contents of the bottle are then poured into 3 liters of hexane and overnight chilled. The resulting precipitate of N- (3-isocyanate- * 1-niethylphenyD-ostadecylcarbamate is collected, reprecipitated from hexane and dried under reduced pressure. The product has a melting point of 78 to 79 ° C.

17.5 g (0.06 mol) l, 2-bis (5-amino-benzimidazoyl-2) ethane, according to Example 1 has been prepared, and 53.4 g (0.12 mol) of the aforementioned carbamate are in 573 g of a neutral HVI oil with a viscosity of 70 SUS

heated to 127 ° C. with stirring in a nitrogen atmosphere. After the reaction has ended, the contents are cooled down to about 110 ° C. The batch is then ground. The obtained grease (Lubricating Grease 1H) contains 11.0% by weight of thickener and has a non-tumbled ASTM penetration (P) of 212 and a WaIk-

Penetration (Pg ₀ ^ ^{from 2} ^ * ^{1 to #}

Example7

The procedure from Example 6 is essentially repeated, However, there are 269 g (1 mol) of stearylamine with 2,4-tolylenediiso-

309807/1339 originally inspected

Cyanate reacted in place of stearyl alcohol, whereby N- (3-isocyanate- * l-methylphenyl) -octadecylcarbamide is formed.

35.5 "g (0.08 mol) of this carbamide are then mixed with 11.7 g (0.04 mol) of 1,2-bis (5-aminobenzimidazoyl-2) ethane, which has been prepared according to Example 1, in 382 g of a neutral HVI oil with a viscosity of 70 SUS is _{reacted at 98 ° S} 9 ° C. After the reaction has ended, the contents are cooled and ground ASTM penetration (P) of 268 and a milled penetration (P ^ _n ) of 283.

B e i s ρ i .e 1 8

The procedure of Example 6 is essentially repeated, but a mixture of stearyl and oleyl alcohols in a molar ratio of 60: k0 is used. The obtained grease (grease 16) 9 "5 wt -.% Thickness center and has a ungewalkte ASTM penetration (P) of 197 and a worked penetration (Pg ₀₎ from 253 to. ■

Example9

The procedure of Example 6 is essentially repeated except that a synthetic hydrocarbon oil is obtained from oligomerized α-olefins with a viscosity of 51, ^ Sayboldt Universal seconds at 98.9 ° C instead of the mineral lubricating oil

30 9 807 / .1339

. ₁₆ _

used. The lubricating grease obtained (lubricating grease 17) contains 14% by weight of thickener and has an uncalculated ASTM penetration (P) of 242 and a worked penetration (Pg ₀ ) of 275.

Example 10

To demonstrate the excellent high temperature behavior of the present grease blends, the greases are selected Examples 6 and 8 two different high temperature bearing aging tests subject. The results of these tests are given in Table V.

Table V.

test

Grease l4 ¹ ^ "grease 16

"Navy High Speed Bearing Test" from Table II, Life of the
Storage% hours

"ABEC Bearing Test" (Fed. Test Mtd. No. 333), 176.7 ° C, 10,000 rpm
Hours until the warehouse fails

4322, 5118

about 4956

386

2)

2)

Contains 1 Qev .-% phenyl-o (-naphthylamine, 0.5 wt .- * oronite 25o

(Dilaurylselenide), 1 wt .- * sodium sebacate and 0.03 wt .- J6 3 amino-1,2,4-triazole.

' Funds from two exams

3 0 9 8 0 7/1339 o ^ri g »nal inspected

Example 11

Table VI below shows other thickeners and lubricating greases according to example 6 to 8.

Table VI

Greasy Acid or Phenylene _D ·. Alcohol or base oil mixtures anhydride diamine amine (cf.

Table I)

Amber 4-nitro-o-2,4-tolylene 80 mol percent acid anhydride phenylene diisocyanate C _Ift H ~ ₇ 0H diamine

20 mole percent

Adipic acid 4-nitro-o- '3,3-di'methyl- 1OO mole percent A' ''

... phenylenediphenyl- · · Cj ₈ H ₃₇ NH ₂ · ;.

diisocyanate

1,2-Cyclo- 4-nitro-o- 2,4-tolylene- 70 mol percent B hexanedicar- bonphenylene diisocyanate ^ 2Ο ^Η 41 ^ΝΗ 2 acid anhydride diamine

30 mole percent

Dodecyl-4-nitro-o-3,3-dimethyl- 100 mole percent B amber-phenylene-biphenyl-4,4 ¹ c H OH acidic anhydride diamine diisocyanate ¹ ^ ³⁷

Phthalic acid 4-nitro-o-2,4-tolylene 75 mol percent anhydride phenylene diisocyanate C ₁₀ H -., OH diamine ^{18 37}

25 mole percent

^C 16 ^H 33 ^OH

Base oil E: mixture of hexadecyl isostearate and esters diraerer Acids

3 0 9 8 0 7/1339 originally inspected

Claims (1)

Claims in the R ₁ and R "hydrocarbon radicals with. 6 to 30 carbon atoms are or OH OH . · · ■ ι Il I ······ 'Rg-XCN-Rjj- and'"R ₇ -XCNR ₅ -ReSte"" · '■' * · 'mean in which Rg' and R "are al'iphatic · hydrocarbon radicals with 6 to 30 carbon atoms, Rj. And R _1. Are divalent aromatic hydrocarbon radicals with 6 to 20 carbon atoms, X a Oxygen atom or the imino group Group is and in the R, a divalent hydrocarbon radical means having 2 to 20 carbon atoms. 2.Verbindungennach claim l, in which R ₁ and R _{3 are} aliphatic hydrocarbon radicals having 12 to 24 carbon atoms. 3.Verbindungen according to claim 1 and 2, in which R ₁ and R ₂ aliphatic 3 09807/1339 owg »nau Are hydrocarbon radicals having 16 to 18 carbon atoms. H. connections according to claim 1 to 3, in which R is a two-volume Is a hydrocarbon radical having 2 to 12 carbon atoms. 5.Verbindungen according to claim 1 to 4, inä3ien R ^ an ethylene group is. , 6. Compounds according to claim 1, in that the radicals Rg and R " contain 12 to 2k carbon atoms. 7. T & rbindungen according to claim 1 or 6, in dsnsn the radicals Rg and. R "contain 16 to 18 carbon atoms. ^ς . . . 8. Compounds according to claim 1, 6 and 7 * indaien the radicals R 1 and R ₁ - are tylene radicals. 9. Process for the preparation of the compounds according to claim 1 to 8, characterized in that one mole of a dicarboxylic acid of the formula HOQC-R, -CQOH or its anhydride is reacted with two moles of a nitro-substituted phenylenediamine, the nitro groups are reduced to Amiaq groups and the product further with two moles of a monoisocyanate R ₁ , p ^ -NGO or with two moles of the reaction product of an aromatic diisoeyanate OCN-Rw ₁ -X-NCO with a monohydric alcohol Rg / yx-QH or a monoamine is implemented. 309807/1339 10. The method according to claim 9 * characterized in that a Phenylenedi.'jünn without nitro groups is used v.'ird, but after the reaction with the dicarboxylic acid or its anhydride will. 11. Use of the compounds according to claims 1 to 10 as thickeners in lubricating greases. 12. The method according to claim 11, characterized in that in addition Additives such as PhenylatBJde or Di- or Trialky] phenols added to ground. 13. Lubricating grease containing a larger amount of a b'l-like Base oil and one for thickening the Bssis oil to a soothing fat consistency Sufficient amount of a. · Compound according to claim 1 to 14. Lubricating grease according to claim 11, characterized in that it additional additives, v; ie pheny! naphthylamines or di- or trialkylphenols, contains. ORIGINAL INSPECTED 309807/1339