SAPS-FREE TWIN-TAIL AMINE DERIVATIVES ADDITIVES FOR LUBRICANT FOR FRICTION MODIFICATION AND WEAR PREVENTION

Abstract

The present invention relates to the use as an antiwear additive (antiwear component) and friction modifier in a lubricant of at least one compound having the following formula (I) wherein: each of R and R, which are identical of different, is a aliphatic group preferably containing between 5 and 23 carbon atoms; and a and b are integers from 0 to 4; and A is a methylene group CH.sub.2; or a carbonyl group C(?O).

##STR00001##

Claims

1. (canceled)

2. (canceled)

3. (canceled)

4. (canceled)

5. (canceled)

6. (canceled)

7. (canceled)

8. (canceled)

9. (canceled)

10. A lubricant composition comprising at least an oil and at least a compound of formula (I): ##STR00017## wherein: each of R and R, which are identical or different, is an aliphatic group; a is an integer selected from 0, 1, 2, 3 and 4; b is an integer selected from 0, 1, 2, 3 and 4; and A is a methylene group CH.sub.2 or a carbonyl group C(?O).

11. A compound having the following formula (I-4): ##STR00018## wherein each of R and R, which are identical or different, is an aliphatic group containing between 5 and 23 carbon atoms.

12. A process for preparing the compound according to claim 11, comprising a step (E) of derivatizing a primary amine RCH(NH.sub.2)R with gluconolactone, wherein R and R are identical or different, and are an aliphatic group.

13. The process of claim 12, which includes, before the step (E), a preparation step (E0) of the primary amine RCH(NH.sub.2)R, by a reductive amination of a fatty internal ketone of formula (II): ##STR00019##

14. The process of claim 13, wherein the fatty internal ketone (II) is obtained through a decarboxylative ketonization of two fatty acids RCOOH and RCOOH.

15. The process of claim 14, wherein the fatty acids RCOOH and RCOOH are bio-based.

16. The lubricant composition of claim 10, wherein R and R contain between 5 and 23 carbon atoms.

17. The lubricant composition of claim 10, wherein a-0 or a=1.

18. The lubricant composition of claim 10, wherein the compound of formula (I) is a 2-[(2-alkylaminoethyl)amino]ethanol derivative having the following formula (I-1): ##STR00020## wherein each of R and R are identical or different.

19. The lubricant composition of claim 18, wherein R and R contain between 5 and 23 carbon atoms.

20. The lubricant composition of claim 10, wherein the compound of formula (I) is a 3-alkylaminopropane-1,2-diol derivative having the following formula (I-2): ##STR00021## wherein each of R and R are identical or different.

21. The lubricant composition of claim 20, wherein R and R contain between 5 and 23 carbon atoms.

22. The lubricant composition of claim 10, wherein the compound of formula (I) is a N-alkylglucamine derivative having the following formula (I-3): ##STR00022## wherein each of R and R are identical or different.

23. The lubricant composition of claim 22, wherein R and R contain between 5 and 23 carbon atoms.

24. The lubricant composition of claim 10, wherein the compound of formula (I) is a N-alkylgluconamide derivative having the following formula (I-4): ##STR00023## wherein each of R and R, which are identical or different, contain between 5 and 23 carbon atoms.

25. The lubricant composition of claim 10, wherein the compound of formula (I) is both an antiwear agent and a friction modifier.

26. The lubricant composition of claim 10, wherein a total content of the at least one compound of formula (I) is between 0.2 and 5% by weight, based on a total weight of the lubricant composition.

27. The lubricant composition of claim 24, wherein the compound of formula (I-4) is both an antiwear agent and a friction reducer in a combustion engine or in transmissions without clutches for electrical vehicles.

28. The lubricant composition of claim 27, wherein a total content of the compound of formula (I-4) is between 0.2 and 5% by weight based on a total weight of the lubricant composition.

29. The process of claim 15, wherein the fatty acids RCOOH and RCOOH are obtained from natural fatty esters.

Description

EXAMPLES

Example 1

Synthesis of a Compound C1 of the Subclass (I-1)

[0063] A compound C1 having the following formula was synthetized according to the protocol described below, from 12-tricosanone which is an internal ketone of formula (II) wherein R?R=(CH.sub.2).sub.10CH.sub.3

##STR00010##

[0064] In a 2L double-jacketed reactor equipped with a mechanical stirrer (propeller with four inclined plows), a condenser and a temperature probe were added: [0065] 100 g of 12-tricosanone (0.295 mole, 1 eq.) [0066] 1L of THE [0067] 61.5 g of aminoethylethanolamine AEEA (0.590 mole, 2 eq)

[0068] The mixture was allowed to stir at room temperature (25? C.) and 100.75 g of titanium tetraisopropoxide (0.354 mole, 1.2 eq.) was added.

[0069] The mixture was then allowed to stir at room temperature overnight and then 500 mL of methanol was added followed by the progressive and careful addition of 11.15 g of NaBH.sub.4 (0.295 mole, 1 eq.).

[0070] The mixture is then stirred at room temperature for 3 hours. 1L of water is then added (precipitation of TiO.sub.2 observed) followed by the addition of 1L of diethyl ether.

[0071] The suspension was then filtered to remove solid TiO.sub.2 and the organic phase was separated from the filtrate.

[0072] The organic phase was washed 3 times with 200 mL of an aqueous NaOH solution (0.5 M), 1 time with 200 ml of water, dried over MgSO.sub.4, filtered and evaporated to afford a pale yellow oil.

[0073] 150 mL of methanol was then added to the crude oil in order to precipitate the insoluble alcohol by-product which is filtered out.

[0074] After methanol evaporation 105.7 g of product is obtained as a pale yellow oil.

[0075] Yield: 84%

[0076] .sup.1H NMR (MeOD. 400 MHZ) ? (ppm): 3.65 (t, J=5.6 Hz, 2H), 2.77-2.60 (m, 6H), 2.49 (quint, J=5.6 Hz, 1H), 1.52-1.19 (m, 40H), 0.91 (t, J=6.8 Hz, 6H).

[0077] .sup.13C NMR (CDCl.sub.3, 101 MHZ) ? (ppm): 61.04, 57.77, 51.46, 49.66, 46.67, 34.29, 32.07, 30.13, 29.82, 29.80, 29.50, 25.95, 22.83, 14.23 (terminal CH.sub.3).

Example 2

Synthesis of a Compound C2 of the Subclass (1-2)

[0078] A compound C2 having the following formula was synthetized according to the protocol described below, from 12-tricosanone which is an internal ketone of formula (II) wherein R?R=(CH.sub.2).sub.10CH.sub.3

##STR00011##

[0079] The reaction was conducted in carefully dried vessels and under an inert argon atmosphere.

[0080] Fresh commercial anhydrous THF and MeOH were used as such.

[0081] In a 1L double-jacketed reactor equipped with a mechanical stirrer (propeller with four inclined plows), a condenser and a temperature probe were added: [0082] 70 g of tricosan-12-one (207 mmol, 1 eq) [0083] 315 ml of anhydrous THF [0084] 38.8 g of 3-Amino-1,2-propanediol (222 mmol, 2 eq) [0085] 89.12 ml of titanium tetraethoxide (413 mmol, 2 eq).

[0086] The milky heterogeneous mixture was stirred at 65? C. at which temperature and turned homogeneous transparent orange. It was allowed to stir at this temperature overnight. The obtained mixture was then cooled down to 40? C. and anhydrous methanol (63 ml) is added into the reactor followed by careful addition of 16.3 g of NaBH.sub.4 (413 mmol, 2 eq) portion wise while monitoring foaming during the addition. The mixture was then stirred at 40? C. for 3 hours.

[0087] After 3 h, .sup.1H NMR analysis in MeOD (sampling 2-3 drops from the mixture, addition of water and diethyl ether, filtration of formed TiO.sub.2 on celite, solvent evaporation and MeOD addition) showed the formation of the expected product.

[0088] The reaction mixture was allowed to cool down to room temperature and water (200 ml) was added slowly to quench NaBH.sub.4 excess followed by 200 ml of diethyl ether.

[0089] The mixture was filtered on celite to remove the large amount of TiO.sub.2 and the solid was washed several times with diethyl ether. The filtrate was decanted and the organic phase was washed 3 times with water and 1 time with brine. The organic phase was dried over MgSO.sub.4, filtered and evaporated to afford crude product as a yellow oil which crystallizes at room temperature.

[0090] The product was then purified thanks to flash chromatography on silica gel using CHCl.sub.3:/PrOH eluent with a gradient going from 100% chloroform to 60/40 CHCl.sub.3:iPrOH (30 ml/min) followed by elution with isopropanol (150 ml/min).

[0091] After solvent evaporation 40.05 g of product analytically pure was obtained in the form of a clear oil which crystallizes as a white solid at room temperature.

[0092] Yield: 47%.

[0093] .sup.1H NMR (MeOD. 400 MHZ) ? (ppm): 3.75-3.67 (m, 1H), 3.57-3.46 (m, 2H), 2.67 (dd, J=12.0 Hz, J=3.7 Hz, 1H), 2.55-2.45 (m, 2H), 1.53-1.39 (m, 4H), 1.39-1.24 (m, 36H), 0.9 (t, J=6.8 Hz, 6H).

[0094] .sup.13C NMR (MeOD, 101 MHZ) ? (ppm): 71.81, 66.47, 59.03, 51.1, 34.75, 33.25, 31.12, 31.09, 30.94, 30.87, 30.84, 30.65, 26.91, 23.91, 14.62 (terminal CH.sub.3).

Example 3

Synthesis of a Compound C3 of the Subclass (1-2)

[0095] A compound C3 having the following formula was synthetized according to the protocol described below, from 16-hentriacontanone which is an internal ketone of formula (II) wherein R?R=(CH.sub.2).sub.14CH.sub.3

##STR00012##

[0096] The reaction was conducted under an inert argon atmosphere.

[0097] In a 1L double-jacketed reactor equipped with a mechanical stirrer (propeller with four inclined plows), a condenser and a temperature probe were added: [0098] 50 g of 16-hentriacontanone (111 mmoles, 1 eq.) [0099] 281 mL of CHCl.sub.3 [0100] 17.73 mL of 3-amino-1,2-propanediol (20.8 g, 222 mmoles, 2 eq.)

[0101] The mixture was then stirred at room temperature and 54.71 mL of Ti(OEt).sub.4 (59.52 g, 222 mmoles, 2 eq.) was added into the reactor.

[0102] The mixture is then stirred at 65? C. overnight and it was observed that during the course of the reaction the mixture becomes homogeneous.

[0103] At the end of the reaction, the temperature was cooled down at 40? C. and 56 mL of anhydrous methanol was added into the reactor followed by the careful and slow addition of 8.74 g of NaBH.sub.4 (222 moles, 2 eq.). Care should be taken as foaming can occur during NaBH.sub.4 addition.

[0104] The reaction medium was then stirred at 40? C. for 3 h00.

[0105] Then the mixture was cooled down at room temperature and 100 ml of water was added followed by 100 mL of diethyl ether. During water addition precipitation of TiO.sub.2 occurred. The suspension was filtered, the solid was washed several times with diethyl ether and the biphasic filtrate was separated. The organic phase was again filtered over celite and was washed with water and brine. The organic phase was then dried over MgSO.sub.4, filtered and evaporated to afford the crude material as a yellow paste (48.9 g).

[0106] The crude was then purified through flash chromatography over silica gel using CHCl.sub.3:isopropanol mixture as the eluent with a gradient going from 100:0 to 50:50. After solvent evaporation 28.75 g of pure product is obtained (54.70 mmoles)

[0107] Yield: 49%

[0108] .sup.1H NMR (MeOD, 400 MHZ) ? (ppm): 3.78-3.64 (m, 1H), 3.62-3.42 (m, 2H), 2.78 (dd, J=11.6 Hz, J=3.6 Hz, 1H), 2.62-2.40 (m, 2H), 1.70-1.11 (m, 56H), 0.90 (t, J=6.4 Hz, 6H).

[0109] .sup.13C NMR (MeOD, 101 MHZ) ? (ppm): 71.78, 66.46, 59.03, 51.08, 34.67, 33.26, 31.08, 31.04, 30.97, 30.95, 30.92, 30.83, 30.80, 30.66, 26.87, 26.85, 23.91, 14.62 (terminal CH.sub.3).

Example 4

Synthesis of a Compound C4 of the Subclass (1-2)

[0110] A compound C4 having the following formula was synthetized according to the protocol described below, from 18-pentatriacontanone which is an internal ketone of formula (II) wherein R?R=(CH.sub.2).sub.16CH.sub.3

##STR00013##

[0111] The reaction was conducted under an inert argon atmosphere.

[0112] A solution of pentatriacontan-18-one (100 g, 0.197 mole, 1 eq.) in 2-Methyl THF (471 mL) was prepared in a 1L double-jacketed reactor equipped with a mechanical stirrer (propeller with four inclined plows) a condenser and a temperature probe.

[0113] To this solution were added under stirring: [0114] 37.06 g of (?)-3-Amino-1,2-propanediol (0.395 mole, 2 eq.) [0115] 105.87 g of titanium (IV) ethoxide (0.395 mole, 2 eq.).

[0116] The solution was refluxed at 80? C. for 24 h and kept at 50? C. overnight under stirring. The reaction mixture was then diluted with MeOH (94 mL), followed by addition of NaBH.sub.4 portion wise (15.55 g, 0.395 mole, 2 eq.) and stirred at 50? C. for 5 h.

[0117] The reaction mixture was further stirred at room temperature over the weekend. The reaction mixture was then quenched with 200 ml of water and the resulting mixture was concentrated under reduced pressure to remove 2-Me THF and methanol. To the residue was added toluene (200 mL) and the mixture was concentrated under vacuum to remove toluene-water azeotrope.

[0118] The resulting white TiO.sub.2 solid was filtered over celite and washed with large amounts of chloroform. The filtrate was washed with DI water and brine solution.

[0119] The combined organic phase was concentrated under reduced pressure and dried. The crude was then purified by flash chromatography over silica gel to yield 30 g of pure product (0.056 mole).

[0120] Yield: 26%

[0121] .sup.1H NMR (CDCl.sub.3, 400 MHZ) ? (ppm): 3.74-3.64 (m, 2H), 3.60 (dd, J=10.4 Hz, J=3.6 Hz, 1H), 2.83 (dd, J=12.4 Hz, J=3.6 Hz, 1H), 2.61 (dd, J=12.4 Hz, J=6.4 Hz, 1H), 2.43 (quint, J=1 Hz, 1H), 1.45-1.15 (m, 64H), 0.86 (t, J=6.8 Hz, 6H).

[0122] .sup.13C NMR (CDCl.sub.3, 101 MHZ) ? (ppm): 69.57, 66.06, 57.68, 49.61, 34.06, 34.01, 31.96, 29.94, 29.74, 29.70, 29.40, 25.72, 22.72, 14.15 (terminal CH.sub.3).

Example 5

Synthesis of a Compound C5 of the Subclass (I-4)

[0123] A compound C5 having the following formula was synthetized according to the protocol described below, from 12-tricosanone which is an internal ketone of formula (II) wherein R?R=(CH.sub.2).sub.10CH.sub.3

##STR00014##

[0124] All the reactions were conducted under an inert argon atmosphere.

Step 1: Reductive Amination of the Internal Ketone

[0125] (Preparation of a Primary Amine of Formula (IV) Wherein Wherein R?R=(CH.sub.2).sub.10CH.sub.3) In a 5L three necked round bottom flask equipped with a magnetic stirrer, a condenser, a temperature probe and a heater was prepared a solution of tricosan-12-one (100 g, 0.295 mol, 1 eq.) in 700 mL of methanol.

[0126] Then NH.sub.4OAc (227.386 g, 2.95 mol, 10 eq.) followed by NaCNBH.sub.3 (74.15 g, 1.18 mol, 4 eq.) are added into the mixture in small portions. The reaction media was stirred at room temperature for 1 hour. Finally, the mixture was heated under reflux for 16 hours. Then the reaction media was cooled down to room temperature and concentrated under vacuum. Finally, 500 mL of a saturated NaHCO.sub.3 aqueous solution and 500 mL of methyl-tertbutyl ether MTBE were added to the residue and the mixture was stirred at room temperature for 1 hour. Concentrated aqueous NaOH solution was added in order to adjust the pH around 9.

[0127] The obtained product (tricosan-12-amine) was extracted with MTBE and the organic phase was washed several times with water and brine. The organic phase is dried with K.sub.2CO.sub.3, filtered and concentrated in vacuum to afford 100.4 g of crude yellow oil.

[0128] The crude was then purified through flash chromatography column over silica gel using dichloromethane: methanol mixture as the eluent with a gradient going from DCM:

[0129] MeOH=100:1 to DCM: MeOH=10: 1+1% Et.sub.3N. After solvent evaporation 93.5 g (0.275 mol) of pure light yellow oil was obtained.

[0130] Yield: 93%

[0131] Step 2: Condensation with 0-gluconolactone

[0132] The reaction is conducted under an inert argon atmosphere.

[0133] In a 250 mL round bottom flask equipped with a condenser, a magnetic stirrer, a heater and a temperature probe were added: [0134] 30 g of tricosan-12-amine as obtained in step 1 (88.3 mmoles, 1 eq.) [0135] 31.47 g of ?-gluconolactone (176.7 mmoles, 2 eq.) [0136] 75 mL of Me-THF

[0137] The mixture was stirred at 80? C. for 6 hours and then is allowed to cool down to room temperature.

[0138] 500 mL of water was then added into the reaction mixture and the product is extracted with 3?500 mL of chloroform.

[0139] The organic phases were gathered, washed again with 500 ml of water, dried over MgSO.sub.4, filtered and the solvent is evaporated to afford 47 g of a pale yellow paste.

[0140] At this stage the crude product still contained residual amounts of the starting amine, therefor the solid was washed with 3?100 mL of ethyl acetate.

[0141] The solid is then dried to remove traces of solvent and 41 g of analytically pure product (79.2 mmoles) is obtained as a white solid.

[0142] Yield: 90%

[0143] .sup.1H NMR (de-DMSO, 400 MHZ) ? (ppm): 7.14 (d, J=9.2 Hz, 1H), 5.32 (d, J=5.2 Hz, 1H), 4.52 (d, J=5.2 Hz, 1H), 4.45 (d, J=5.2 Hz, 1H), 4.32 (d, J=7.6 Hz, 1H), 4.32 (t, J=5.6 Hz, 1H), 3.97 (dd, J=4.8 Hz, J=4.0 Hz, 1H), 3.92-3.84 (m, 1H), 3.75-3.62 (m, 1H), 3.58 (ddd, J=10.8 Hz, J=5.6 Hz, J=2.8 Hz, 1H), 3.52-3.42 (m, 2H), 3.35 (dt, J=10.8 Hz, J=5.6 Hz, 1H), 1.44-1.12 (m, 40H), 0.85 (t, J=7.2 Hz, 6H).

Example 6

Synthesis of a Compound C6 of the Subclass (I-4)

[0144] A compound C6 having the following formula was synthetized according to the protocol described below, from 16-hentriacontanone which is an internal ketone of formula (II) wherein R?R=(CH.sub.2).sub.14CH.sub.3

##STR00015##

[0145] All the reactions were conducted under an inert argon atmosphere.

Step 1: Reductive Amination of the Internal Ketone

[0146] (Preparation of a Primary Amine of Formula (IV) Wherein Wherein R?R=(CH.sub.2).sub.14CH.sub.3)

[0147] Same protocol as described in step 1 of example 1 has been followed, but starting from hentriacontan-16-amine instead of tricosan-12-amine.

[0148] Step 2: Condensation with o-gluconolactone

[0149] The reaction was conducted under an inert argon atmosphere.

[0150] In a 250 mL round bottom flask equipped with a condenser, a magnetic stirrer, a heater and a temperature probe were added: [0151] 30.0 g of hentriacontan-16-amine (66.4 mmoles, 1 eq.) [0152] 11.8 g of ?-gluconolactone (66.4 mmoles, 1 eq.)

[0153] 75 mL of Me-THF

[0154] The mixture was stirred at 80? C. for 2 days and then was allowed to cool down to room temperature.

[0155] 500 ml of water was then added into the reaction mixture followed by 500 mL of chloroform. The obtained precipitate is filtered out and the solid was washed with 2*100 ml of ethyl acetate.

[0156] The solid was then dried to remove traces of solvent and 32 g of analytically pure product (51 mmoles) is obtained as a white solid.

[0157] Yield: 77%

[0158] .sup.1H NMR (de-DMSO:CDCl.sub.3, 400 MHZ) ? (ppm): 6.87 (d, J=9.2 Hz, 1H), 5.25 (d, J=4.8 Hz, 1H), 4.46 (d, J=4.8 Hz, 1H), 4.40 (d, J=4.8 Hz, 1H), 4.24 (d, J=7.6 Hz, 1H), 4.15 (t, J=5.6 Hz, 1H), 4.05 (dd, J=4.0 Hz, J=3.2 Hz, 1H), 4.01-3.96 (m, 1H), 3.77-3.66 (m, 1H), 3.64-3.50 (m, 3H), 3.52-3.42 (m, 1H), 1.55-1.10 (m, 56H), 0.82 (t, J=6.8 Hz, 6H).

[0159] .sup.13C NMR (de-DMSO:CDCl.sub.3, 101 MHZ) ? (ppm): 171.9, 74.54, 73.60, 71.80, 70.26, 63.82, 48.57, 35.05, 31.82, 29.59, 29.55, 29.52, 29.24, 25.90, 25.86, 22.61, 14.31 (terminal CH.sub.3).

Example 7

Antiwear and Friction Modifying Performances

[0160] The synthetized compounds C1-C6 have been tested according to the following protocols (4 ball wear test and Friction test defined hereinafter).

[0161] A further compound, herein referred as compound C7, has been tested according to the same protocol for the friction test. This compound C7, purchased from Asta Tech Inc, is 3-(isopropylamino)propane-1,2-diol (CAS #6452-5-9) of formula:

##STR00016##

[0162] For the sake of comparison, the following additives have been tested in the same conditions: [0163] GMO: Glycerol Monooleate [0164] Oleyl amide [0165] MoDTC (Molybdeneum Dithiocarbamate): 55-65% by weight of a MoDTC mixture of Molybdenum, bis [N, N-bis(2-ethylhexyl)carbamodithioato-kS, kS]dioxodi-m-thioxodi- and Molybdenum, bis(N, N-ditridecylcarbamodithioato-KS,KS)dioxodi-u-thioxodi-, branched in a mineral oil

4 Ball Wear Test (for the Evaluation of Wear Protection)

Test Made According to ASTM D4172

[0166] All the tests run for 60 min at 75? C. under a 40 kg load, at a 1200 rpm speed.

[0167] Each candidate is added at 1 wt % in a Group II mixture base oil of 45 wt % of a base oil at 6.5 cSt at 100 C and 55% of a base oil at 12 cSt at 100? C. to meet an overall kinematic viscosity at 9 cSt at 100? C.

Friction test:

[0168] Friction has been evaluated using a HFRR (High Frequency Reciprocating Rig) under the following conditions:

[0169] slide ball on disc: metal/metal under a 200 g load at a 1000 microns stroke, at 40? C. for 15 min and then ramped to 150? C. @ 2? C./min for 55 min.

[0170] Each candidate was added at 1 wt % in a Group III base oil with a kinematic viscosity at 8cSt at 100? ? C. to mimic a typical engine oil (SAE 20).

[0171] The obtained results are reported in the following Table 1:

TABLE-US-00001 TABLE 1 Results Antiwear: Friction test: Tested scar diameter coefficient of compound (mm) friction @ 150? C. C1 0.53 0.176 C2 0.57 0.127 C3 0.58 0.135 C4 0.54 0.122 C5 0.34 0.085 C6 0.41 0.076 C7 - not tested - 0.171 GMO 0.75 0.094 (COMPARATIVE) Oleyl amide (COMPARATIVE) 0.55 0.105 MoDTC 0.42 0.076 (COMPARATIVE)