US3809706A - N-substituted fatty acid amide lubricants - Google Patents

Abstract

THIS INVENTION RELATES TO N-ACYLMORPHOLINES AND NMONO AND N,N-DISUBSTITUTED FATTY ACID AMIDES AND TO SIMILAR DERIVATIVES OF EPITHIOAMIDES WHICH ARE USEFUL AS BASE AND EXTREME PRESSURE LUBRICANTS AND ADDITIVES.

Description

United States Patent Otfice 3,809,706 Patented May 7, 1974 3,809,706 N-SUBSTITUTED FATTY ACID AMIDE LUBRICANTS Frank C. Magne, Robert R. Mod, and Gene Sumrell, New Orleans, La., and Winfred E. Parker, Philadelphia, Pa., assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Original application Aug. 31, 1971, Ser. No. 176,734, now Patent No. 3,746,644. Divided and this application Apr. 6, 1973, Ser. No. 348,802

Int. Cl. C071? 9/02, 9/10 U.S. Cl. 260-403 1 Claim ABSTRACT OF THE DISCLOSURE This invention relates to N-acylmorpholines and N- mono and N,N-disubstituted fatty acid amides and to similar derivatives of epithioamides which are useful as base and extreme pressure lubricants and additives.

This is a division of application Ser. No. 176,734 filed Aug. 31, 1971, now Pat. No. 3,746,644.

A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to certain compounds which are N-fatty acyl derivatives of primary and secondary amine and N-substituted acyl derivatives of primary and secondary amines which have exhibited utility as base lubricants, extreme pressure lubricants or lube additives. More particularly, this invention relates to N- and N,N-disubstituted long chain aliphatic amides the acyl component of which is a normal, branched, or substituted alkenoic or alkanoic acyl 'group containing from 16 to 22 carbon atoms the amide nitrogen of which may be derived from an alkyl amine, dialkyl amine, alkylalkoxyalkylamine, dialkoxyalkylamine or nitrogen heteroalicyclic. Typical amines are butylamines, dibutylamines, N-methyl-alkoxyethyl amine, di-ethoxyethyl amine, and morpholine. The acyl substituent referred to may be divalent sulfur or pentavalent phosphorus. I

We have discovered that many of the simple N-alkyl and N,N-dialkyl or N-alkyl-N-alkoxyalkyl amides of the C to C alkeneoic or alkanoic fatty acids are good base lubricants. We have further discovered that the introduction of divalent sulfur into the fatty acid moiety imparts excellent extreme pressure lubricant characteristics to such compounds. In particular we have found the epithio group to be most eifective. We have also observed that the introduction of both hydroxy and alkyl phosphato groupings alpha to each other also imparts extreme pressure lubricant characteristics to the compound.

In addition it was noted that the above hydroxyphosphato compound and its mercapto analog N-[9(10)- mercapto-(9)IO-dibutylphosphato]stearamide were efiective antiwear compounds and additives.

Inclued among the specific compounds operable as base lubricants are N-methyl-N-butyloleamide, -N-ethoxyethoxyethoxy propyloleamide, N-ethoxyethoxy propyloleamide, N-methoxyisopropyloleamide, N-rnethoxyethyloleamide. Compounds showing particular promise as extreme pressure lubricants. or additives are N,N-dibutyl- 9, 10-epithiostearamide, N,N-dibutyl-9, 10-12, 13-diepithiostearamide, 9, 10-epithiostearoy1 morpholine, N-

ethoxyethoxyethoxypropyl-9, IO-epithiostearamide, n- 9, 10-12, 13-diepithiostearoylmorpholine and N-[9(10)- hydroxy-9 10) -dibutylphosphato] stearamide.

Compounds showing particular promise as antiwear additives are N,N-dibutyl-[9( l0)-hydroxy-(9) IO-dibutylphosphato]stearamide and N,N-[9(l0)mercapt0-(9) 10- dibutylphosphatostearoyl]morpholine.

Example 1 N-methyl-N-butyloleamide.-- grams (0.33 mole) of oleoyl chloride was added dropwise and with stirring to a mixture of 29 grams (0.33 mole) of N-methyl-N- butylamine and 27 grams (0.33 mole) of pyridine. Stirring was continued until the heat of reaction subsided. The solid pyridine hydrochloride was filtered otf and the filtrate was washed successively with aqueous HCl and water until acid free. It was dried stripped, percolated through an activated alumina column, and the product removed from the percolate by stripping ofi the solvent. Analysis of the product (percent): C, 78.87 (theory 78.63); H, 13.02 (theory 12.82); N, 3.96 (theory 3.99).

Example 2 N,N-dibutyloleamide.-'Ihis material was prepared by the procedure of Example 1 from 100 grams (0.33 mole) of oleoyl chloride 42.5 grams (0.33 mole) of di-n-butylamine and 27 grams (0.33 mole) pyridine. Analysis of the product (percent): C, 78.94 (theory 79.25); H, 13.16 (theory 13.06); N, 3.44 (theory 3.56) confirm the preparation.

Example 3 Ethoxyethoxyethoxy propyloleamide.--This material was prepared by the procedure of Example 1 from 100 grams (0.33 mole) of oleoyl chloride, 73.0 grams (0.33 mole) ethoxyethoxyethoxy-propylamine and 27.0 grams (0.33 mole) pyridine. Analysis (percent): C, 71.84 (theory 72.04); H, 11.80 (theory 11.80); and N, 2.96 (theory 2.90) confirm the preparation.

Example 4 Ethoxyethoxypropyloleamide.This material was prepared by the procedure of Example 1 from 100 grams (0.33 mole) of oleoyl chloride, 58.3 grams (0.33 mole) ethoxyethoxypropylamine and 27.0 grams (0.33 mole) of pyridine. Analysis (percent): C, 71.45 (theory 73.80); H, 11.87 (theory 12.07); and N, 2.92 (theory 3.18) confirm the preparation.

Example 5 Methoxyisopropyloleamide-This material was prepared by the procedure of Example 1 from 100 grams (0.33 mole) of oleoyl chloride, 29.3 grams (0.33 mole) methoxyisopropylamine and 27.0 grams (0.33 mole) pyridine. Analysis (percent): C, 73.15 (theory 74.99); H, 12.01 (theory 11.93); and N, 3.67 (theory 3.97) confirm the preparation.

Example 6 Methoxyethyloleamide.--This material was prepared by the procedure of Example 1 from 100 grams (0.33 mole) of oleoyl chloride, 24.4 grams (0.33 mole) of methoxyethylamine and 27.0 grams (0.33 mole) pyridine. Analysis (percent): C, 73.08 (theory 74.55); H, 11.98 (theory 11.83); and N, 3.31 (theory 4.14) confirm the preparation.

Example 7 Oleoylmorpholine.-This material was prepared by the procedure of Example 1 from 100 grams (0.33 mole) of oleoyl chloride, 28.7 grams (0.33 mole) of morpholine and 27.0 grams (0.33 mole) of pyridine.

3 Example 8 N,N-dibutyloleamider-This product was'p'r'epared fol lowing the exact procedure of Example 2 except for the substitution of oleoyl chloride by linoleoyl chloride.

Example 9 N,N-dibutyl-9,10-epithiostearamide.-l20 grams (0.30 mole) of N,N-dibutyloleamide was epoxidized by the addition with stirring of 62.0 grams (0.36 mole) of metachloroperbenzoic acid in 630 ml. of chloroform. Reaction was continued for 1 hour beyond final addition and the excess peracid destroyed by a small amount of a 10% solution of Na SO The metachlorobenzoic acid was removed by a NaHCO Wash, followed by water washing. The CHCl solution was then dried with anhydrous Na SO and the CHCl stripped off to recover the product N,N dibutyl-9,10-epoxystearamide, oxirane content 3.45% (theory 3.91%). 100 grams (0.24 mole) of this product was added to a well stirred slurry of 55.7 g. (0.73 mole) of thiourea and 89.5 g. (0.73 mole) of benzoic acid in acetone. Stirring was continued for 3 hours beyond the terminal addition whereupon the benzoic acid was washed out with 38.8 g. (0.36 mole) of Na CO and the organic product extracted with hexane. The

organic phase extract was dried and stripped to recover the product N,N-dibutyl-9,10-epithiostearamide containing 6.41% sulfur (theory 6.67%

Example 10 N (9,10 epithiostearoyl)morpholine.--This product was prepared by the exact procedure described in Example 9 except for the substitution of oleoylmorpholine for the N,N-dibutyloleamide of Example 9. Analysis of product showed (percent): C, 71.22 (theory 69.34); H, 11.22 (theory 1077); N, 3.66 (theory 3.68); S, 3.44 (theory 7.80).

Example 11 N,N dibutyl-9,10,12,13 diepithiostearamide.-'Ihis product was prepared following the procedure described in Example 9 except for the replacement of the N,N dibutyl oleamide of Example 9 by N,N-dibutyllinoleamide, and a doubling of the molar ratios of all reagents. The product analyzed as follows (percent): C, 69.64 (theory 68.57); H, 10.93 (theory 10.76); N, 3.10 (theory 3.07); S, 11.7 (theory 14.06).

Example 12 N-ethoxyethoxyethoxypropyl-9,l0-epithiostearamide.- To 166 g. of N-ethoxyethoxyethoxypropyl oleamide, Example 3, was added dropwise and with stirring 73.8 g of m-chloroperbenzoic acid in 800 ml. of CHCl The spent m-chloroperbenzoic acid was removed with 10% aqueous NaHCO and the epoxide recovered by drying and stripping off the CHCl 171 g. of this epoxide was added dropwise to a slurry of 56 g. thiourea in 1000 ml. of acetone and the concurrent addition of 43.4 g. of glacial acetic acid and the reaction mixture stirred for 3 hours. The glacial acetic acid was neutralized with Na CO and the episulfide, N-ethoxyethoxyethoxypropyl- 9,10-epithiostearamide, extracted with Skellysolve B and washed, dried, and stripped. Its elemental analysis was (percent): C, 67.1 (66.52); H, 11.42 (10.88); N, 2.67 (2.87); S, 2.29 (6.57).

Example 13 N ethoxyethoxyethoxypropyl 9(10)mercaptostearamide.--173 g. of N-ethoxyethoxyethoxypropyloleamide in CCL; was treated in the cold with a CCL, solution con- 5 4 extracted with hexane; washed, dried, and stripped. Elermental..analysis-aoftthe productwas (percent): C, 66.3

(66.5); H, 11.1 (10.9); N, 2.7 (2.9); S, 4.4 (6.8).

Example 14 N,N dibutyl g 9( 10) [dibutylphosphono] stearamide.- g. of N,N-dibutyloleamide, Example 2, 148 g. of dibutyl vphosphite, and 1.29 of benzoyl peroxide catalyst were heated at C. for 3 /2 hours. Additional units of 1.29'g. of benzoyl peroxide was added after the first and second hours of reaction time. The excess dibutyl phosphite'wasthen removed by distillation at reduced pressure, 0.45 mm. Hg. The stillpot contents showed strong adsorption bonds at 8, 9.3, and 9.7 microns characteristics of the phosphonate group. The elemental analysis was (percent): C, obs. 71.46 (69.50); H, obs. 12.42 (11.92); N, obs. 2.20 (2.38); P, obs. 4.24 (5.28) respectively.

Example 15 N-9,10-12,13-diepithiostearoylmorpholine-This prodnot was prepared by the same procedure described in Example 9 except'for the substitution of linoleoyl morpholine for the N,N-dibutyloleamide of Example 8 and the doubling of molar proportions of the m-chloro perbenzoic acid in the epoxidation step and the thiourea and benzoic acidin the epithioation step. The elemental analysis was (percent): C, obs. 68.89 (63.92); H, obs. 10.26 (9.44.); N, obs. 3.29 (3.38); S, obs. 4.00 (15.49) respectively.

Example 16 N,N-dibutyl- [9 l0) -hydroxy- (9 10-dibutylphosphato] stearamide.44.7 g. of dibutylhydrogen phosphate was added to 182.2 g. of N,N-dibutyl-9,10-epoxystearamide at 90-95 C. with stirring. Reaction conditions were con-. tinued for 3 /2 hours after termination of the addition. The reaction product was dissolved in commercial hexane andthe unreacted dibutyl hydrogen hosphate neutralized and washed out with portions of aqueous 10% NaI-IC-O' followed by several water washes. Acidulation of th hexane phase with diluted HCl followed by several water washes, drying and stripping, yielded the product. Elemental analysis was (percent): C, obs. 66.56 (65.91); H, obs. 11.04 (11.30); N, obs. 2.90 (2.26); P, obs. 3.04 (4.20). I Example 17 N [9(10)mercapto (9)1O-dibutyIphosphatostearoyl] morpholine.--l2 g. of dibutylhydrogen phosphate was added dropwise with stirring to 51.0 g. of (9,10-epithiostea'royDmOrphoIine, the preparation of Example 10, at 85590 C. and the heating and stirring continued for 3 hours beyond the terminal addition. The reaction product was dissolved in commercial hexane and any excess or unreacted" was neutralized and washed out with aqueous 10% NaHCO .'The 'hexane extract was washed several times with water dried and stripped. The elemental analysis of the product was (percent): C, obs. 66.74 (69.36); H, obs. 10.69 (11.05); N, obs. 2.89 (3.32); S, obs. 3.27 (2.17); P,- obs. 1.68 (2.10) respectively.

Example 18 The compounds prepared in accordance to the procedures given in Examples 1 through 7 were evaluated as base lubricants 'in' the Shell Four-Ball Wear tests following amodified procedure of ASTM D2266-67. The resulting scar diameter on the balls after running at 600 r.p. m. for 1 hour at C. and 50 kg. load were compared with the scars obtained using commercial lubricants such as Aeroshell Mil-L-708 (di-Z-ethylhexyl sebacate and additive), Gulfpride, single G, MS, multiviscosity, and 100 sec. parafiin oil. The results of these tests are reported in Table I.

TABLE I.--ANTIWEAR LUBRICANT PROPERTIES OF FATTY ACID AMIDES Avg. wear scar, mm.

With- With out addiaddi- Compound tive tive Additive 1.-... N,N-bis(2-ethoxyethyl) 0. 597 0. 735 N,N-di-butyl-9,

oleamide. lo'epithiostearamide.

2..--. N,N-dl-n-butyl-9,10-epi- 0.842 None.

thiostearamlde.

3.-... Oleoy nnorpholine 0.623 0.658 Do.

N,N-dlimethyloleamide. 0. 797 0. 987 Do. ,N-c i-n-propyloleamide. 0. 908 0. 885 Do. 6- N,N-diexylolea1n1de-..-. 0. 893 0. 898 Do. ,N-dibutylerucamrde... 0.758 0. 798 Do. 8.---- N,N-di-n-buty1 amide of 0. 798 0. 958 Do.

sel. hydrogenated cottonseed fatty acids.

9. N,N-bis(2-methoxyethyl) D0.

olearm'de.

10. N,Ndihutyloleamide N-oleoyl-i-propylpiperidine.

. Morpholide of sel. hydrogenated cottonseed fatty acids.

13. N-rnethyl-N-butyloleamlde- 14. N 'ethoxyethoxyethoxypropyloleamide.

15- N-ethoxyethoxypropyleamide.

16. N-methoxyisopropyloleamide.

17- N-methoxyethyloleamlde. 0. 420

18. 102 sec paraflin oil 0. 902 N-rnethoxyethyloleamide.

19...- D.O. 0.906 Do.

20- N,N-dibutyl-9(10)-carbo- 0 610 butoxyoctadeeanamide.

21.-.- 102 sec paratfin oil 0.818 N,N-d1butyl-9(10)- carbobutoxyoctadeeenamide.

22.-.. D.0.S 0.945 Do.

23- N -[9(10)mercapto-(9)10- 0. 615

dibutylphosphatostearoyl] morpholine.

24. 102 see paraflin oil 0. 552 N-[9(10)mercapto- (9)10-dibuty1- phosphatestearoy11morpholine.

25.-.. D.O.S 0.535 Do.

26- N,N-dibutyl-[9(10) -hy- 0. 498

droxy-(9)10 1ibutylphosphato]stearamide.

27. 102 sec paratfin oil 0. 498 N,N-dibutyl-[9 ()-hydroxy- (9)10-dibuty1- phosphate] stearamlde.

28...- D.O.S D0.

phosphono1steeramlde.

30- N-ethoxyethoxyethoxy- 31. N-ethoxyethoxyethoxypropyl-9(10)mercaptostearamide.

32. N-(9,10-12 13-diepithlostearoyl morpholine.

33- Bis(2-ethylhexyl)sebacate.

34- 100 sec paratfin oil Aeroshell (Mil-7808) 0 36..-- Gulipride, Single G, MS,

multiviscosity.

37- 100 sec paraffin oil 0. 813 N,N-dlbutyl-9, 10-12,13-diepithiostearamide.

38. Bis(2-ethylhexyl)sebacate 0.836 Do.

39- 100 see paraflin oil 0. 723 N-9,10-ep1th10- stearoyl morpholine.

40.... Bls(2-ethylhexyl)sebacate 0.915 Do.

41. 100 sec paraffin oil 0. 917 N,N-dibutyl9,

10-dich1orostearamlde.

42- Bis(2-ethylhexyl)sebacate 0. 848 Do.

It can be seen from the data presented that the N- alkoxyalkyl and N,N-di(alkoxyalkyUoleamides, without the assistance of additives, exhibited wear characteristics (i.e., low scar diameters) comparable to the commercial controls Aeroshell and Gulfpride, which do contain additives to improve performance. N,N-dibutyl-[9(10)-hydroxy-(9)IO-dibutylphosphato]stearamide and N-[9(10) mercapto-(9)1O dibutylpho sphatostearoyl]morpholine 6. not only exhibit low wear characteristics in themselves but also impart as additives such characteristics to paraffin oil and DOS base lubricants.

Example 19 TABLE IL-EXTREME PRESSURE TESTS (ASTM D2596-67T) Weld point No addi- With Compound tive 5% #2 1 N,N-bls(2-ethoxyethyl)oleamlde 120 170 2- N,N-di-n-butyl-Q,m-epithiostearamide 3- Oleoylmorpholine. 4 N,N-dimethyloleamide 5 N,N-di-n-propylol'eamide 6. N,N-di-n-hexyloleamide 7 N,N-di-n-butylerucamide 8. N,N-di-n-butyl amide 0t hydrogenated cottonseed fatty acids. 9 N,N-bis(2-methoxyethyl)oleamide 10 N-methy1-N-butyl,o1eamide 11 N,N-dibuty1-9,10-epithiostearamide 12- N,N-dibutyl-9,10-12,13-diepithiostearamlde...- 13 N-ethoxyethoxyethoxypropyloleamide 14 N-ethoxyethoxypropyloleamide. 15 N-methoryisopropyloleamide 16. N-methoxyethyloleamide 17. N-QJU-epithiostearoylmorpho 18. B1s(2-ethylhexyl)sebacate 19- 100 sec paraflin oil. 20 SAE commercial hypoid flui TABLE III Evaluation of N,N-dibutyl9,10-12,13-d.ieplthiostearamlde as an additive and as a base oil in extreme pressure tests. (ASTM D2596-67T) Wear Per cent Load, scar, Base oil additive kg. mm.

sec paraflin oil 5 140 1. 90 Do 5 200 2. 35 5 220 2. 75 5 240 4 Weld 5 1 51 5 180 1. 59 5 1 190 2. 47 5 200 I Weld 10 240 2. 88 10 260 3. 55 10 270 Weld N,N-dibuty1-9,10-12,13-d1epithiostearamide None 120 1. 38 Do.-. None 160 1. 61 Do--. None 200 1. 89 Do. None 280 2. 13 Do.-. None 320 2. 47 Do- None 360 2. 70 Do--- None 400 2. 88 Do None 440 7 Weld Extreme pressure tests on N-ethoxyethyoxyethoxypropyl-9,10-epithiostearemide (PC-O-No. 7682) Applied Avg. load, scar, Base oil Additive kg. mm.

None 120 1.05 None 160 v 1. 75 None 240 2.35 None 300 2. 19 None 340 2.55 None 360 2. 62 None 380 Weld 7682 (5%) 120 2.28 (5%) 2. 46 7682 (5%) Weld 682 (5%) 120 2.23 7682 (5%) 140 2.44 (5 150 Weld See footnotes at end of table.

TABLE IIIContinued TABLE lll continrued Extreme pressure tests on N-[9(10)-mercapto-9(10)-dibutylphosphato igfg 22i stearoyflmorpholiue (PC-O-No. 7687) I Base 011 Additive kg. mm. None 120 608 None 160 1. 45 Extreme pressure tests on N-ethoxyethoxyethox ropyl-9(l0)-mercapto- None 200 1. stearamide (P C-O-No. 768 None 240 1. None 280 3. 36

None 200 1. 54

None 300 2. 26 Extreme pressure tests on N,N-dibutyl-9(l0) -carbobutoxyoetadecan None 400 2. 25 amide (PC-O-No. 7688) None 450 2. 15 None 500 I 2. 15 None 1. 92 None 2. 18 120 1. 97 None 2. 45 140 2. 35 None Weld 150 2. 54 160 Weld 1 Incipient seizure. 120 1 68 1 Test stopped because of extreme decomposition. Did not weld. 140 8 Test stopped because of extreme decomposition and noxious fumes. 160 5g 15 Did not weld. 72 4 5 seconds. m 6 4 seconds.

a 0 10 seconds.

1 46 seconds.

Extreme pressure tests on N-(9,10-12,l3-diepithiostearoyDmorpholine I (PC-O-No. 7684) N 200 2 21 20 TABLE IV v N83: 2 0 2: 33 Evaluation of N-9,1(}epithiostearoyl morpholine as an additive and as 9.

N 340 2 43' base oil in extreme pressure tests (ASTM D 2596'67T) N 2. 75 N832 2, 90 Percent Load, Wear N 500 2 2' 9g Base oil additive kg. scar, mm.

7684 (5%) i 100 2. 23 I 25 100 see. parafiin oil 5 120 2.00 7684 (5%) 120 2.61 D0 5 140 2. 80 7684 (5%) 2. 74 5 160 3. 25 7684 (5%) Weld 5 180 l Weld 7 50 e 5 160 94 7684 (57) 140 2. 53 5 180 00 3 59;? 160 77 5 200 Weld 5 170 C1 e None 120 0. .70 None 200 2. 13 Extreme pressure tests on N,N-dibutyl- (l0)-(dibutylphospnouo N n 240 2. 43 stearamide (PC-O-No. 7685) None 300 68 None 380 a Weld 76 85 None 120 3. 05 7685 140 50 1 10 seconds. I 5 seconds. 3 50 seconds.

7685 None Weld Extreme pressure tests on N,N-dibutyl-[9(10)-hy droxy-9(llD-dibutyl- 40 We claimh h t t 'd PC-O-N .7686 p 1. The compound N,N-d1butyl-9(10)-[d1butylph0s 5 83: gig I 2%; phono]stearamide useful as a lubricant base. 1 3 2 2'?) f 31 d 0119 None 360 Weld 45 Re f e 100 s par fl 1332 (3%) 2 3.33 3 189 2 s??? STA'ZES r 0 ,6 8 1 Kni-g tet a 260-403 38: .1323? Ei; hi3 215 3,211,766 10/1965 Magne et a1. 260403 no.5 7686 (5%) 120 L95 3,538,123 11/1970 Mod et a1. 260-403 D.O.S 7686 5% 140 2.86 50 D.O.S- 7686 0 ELBERT L. ROBERTS, Primary Examiner D.0.S rose (5% Weld