US3801609A - 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 Office 3,801,609 Patented Apr. 2, 1974 U.S. Cl. 260-4025 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 phosphorous.

We have discovered that many of the simple N-alkyl and N,N-dialkyl r 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 effective. 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 hydroxy-phosphato compound and its mercapto analog N-[9(10)-mercapto-(9) IO-dibutylphosphato]stearamide were effective antiwear compounds and additives.

Included among the specific compounds operable as base lubricants are N methyl-N-butyloleamide, N-ethoxyethoxyethoxy propyloleamide, N-ethoxyethoxy propyloleamide, N-methoxyisopropyloleamide, N-methoxyethyloleamide. 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-epithiostearoyl morpholine, N-ethoxyethoxyethoxypropyl 9,10 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(10)-hydroxy-(9)IO-dibutylphosphato] stearamide and N,N-[9(10) mercapto-(9) 10- dibutylphosphatostearoyl]morpholine.

EXAMPLE 1 N-rnethyl-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 off 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 off the solvent. Analysis of the product: Percent C, 78.87 (theory 78.63); percent H, 13.02 (theory 12.82); percent N, 3.96 (theory 3.99).

EXAMPLE 2 N,N-dibutyloleamide.--This 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-nbutylamine and 27 grams (0.33 mole) pyridine. Analysis of the product: Percent C, 78.94 (theory 79.25); percent H, 13.16 (theory 13.06); percent N, 3.44 (theory 3.56) confirm the preparation.

EXAMPLE 3 Ethoxyethoxyethoxy propylo1eamide.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) ethoxyethoxyethoxypropylamine and 27.0 grams (0.33 mole) pyridine. Analysis of 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. Analyses of percent C, 71.45 (theory 73.80); percent H, 11.87 (theory 12.07); and percent 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 of percent C, 73.15 (theory 74.99); percent H, 12.01 (theory 11.93); and percent N, 3.67 (theory 3.97) confirm the preparation.

3 EXAMPLE 6 Methoxyethyloleamide.-'Ihis 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 of percent C, 73.08 (theory 74.55); percent H, 11.98 (theory 11.83); and percent 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.

EXAMPLE 8 N,N-dibutyloleamide.-This product was prepared following the exact procedure of Example 2 except for the substitution of oleoyl chloride by linoleoyl chloride.

EXAMPLE 9 N,N-dibutyl-9,10-epithiostearamide.-120 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. (0.75 mole) of thiourea and 89.5 g. (0.72 mole) of benzoic acid in acetone. Stirring was continued for 3 hours beyond the terminal addition whereupon the henzoic 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,lo-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); percent H, 11.22 (theory 10.77); percent N, 3.66 (theory 3.68); percent S, 3.44 (theory 7.80).

EXAMPLE 11 N,N dibutyl 9, 10-12, l3-diepithiostearamide.-This product was prepared following the procedure described in Example 9 except for the replacement of the N,N-dibutyloleamide 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); percent H, 10.93 (theory 10.76); percent N, 3.10 (theory 3.07); percent S, 11.7 (theory 14.06).

EXAMPLE 12 N-ethoxyethoxyethoxypropyl-9, 10-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 01f 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 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(l0)mercaptostearamide.17 g. of N-ethoxyethoxyethoxypropyloleamide in CCL, was treated in the cold with a CCl, solution containing 60.9 g. of bromine. Any unreacted bromine was re moved by a thiosulfiate wash. 14 g. of the resulting dibromo compound was added dropwise to a well stirred solution of 72 g. of Na S-9H O in dimethylsulfoxide maintained at C. Stirring was continued at 80 C. for 3 hours. Water was added and the reaction product was extracted with hexane; washed, dried, and stripped. Elemental analysis of the product was C=66.3 (66.5), H=11.1 (10.9), N=2.7 (2.9), S=4.4 (6.8).

EXAMPLE l4 N,N-dibutyl 9(10) [dibutylphosphono]stearamide. g. of N,N-dibutyloleamide, Example 2, 148 g. of dibutyl phosphite, and 1.29 g. 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 was then 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 C=obs 71.46 (69.50), H=obs 12.42 (11.92), N: obs 2.20 (2.38), P=obs 4.24 (5.28) percent respectively.

EXAMPLE l5 N-9,10-1'2,13-diepithiostearoylmorpholine.--This' product 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-chloroperbenzoic acid in the epoxidation step and the thiourea and benzoic acid in the epithioation step. The elemental analysis was C=obs 68.89 (63.92), H=obs 10.26 (9.44), N=obs 3.29 (3.38), S=obs 4.00 (15.49) percent re spectively.

EXAMPLE l6 N,N-Dibutyl- [9 10 -hydroxy- 9) 10-dibutylphosphato1- 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 continued for 3 /2 hours after termination of the addition. The reaction product was dissolved in commercial hexane and the unreacted dibutyl hydrogen phosphate neutralized and washed out with portions of aqueous 10 NaHCO followed by several water washes. Acidulation of the hexane phase with diluted HCl followed by several water washes, drying and stripping, yielded the product. Elemental analysis was, C=obs 66.56 (65.91), H=obs 11.04 (11.30), N=obs 2.90 (2.26), P|=obs 3.04 (4.20).

EXAMPLE 17 N [9(10)mercapto-(9) 10-dibutylphosphatostearoyl] morpholine.-12 g. of dibutylhydrogen phosphate was added dropwise with stirring to 51.0 g. of (9,10-epithiostearoyl)morpholine, the preparation of Example 10, at 85-90 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 C=obs 66.74 (69.36), H=obs 10.69

5 (11.05), N=obs 2.89 (3.32), S=bs 3.27 (2.17), P=obs 1.68 (2.10 percent respectively.

EXAMPLE 18 The compounds prepared in accordance to the procedures given in Example 1 through 7 were evaluated as TABLE I Antiwear lubricant properties of fatty acid amides Avg. wear scar, mm.

Without With Compound additive additive Additive 1 N, N-bis(Z-ethoxyethyDoleamide 0. 597 0. 735 N, N-di-buty1-9, 10-epithiostearamide. 2.-. N 0.842 None. 3-.- 0. 623 D0. L 0. 797 Do. 5... N, N-di-n-propyloleamide 0. 908 Do. 6 N, N-di-n-hexyloleamide 0. 893 Do. 7... N, N-din-butylerucamide 0. 758 Do. 8... N, N-di-n-butyl amide of sel. hydrogenated cottonseed fatty acids..." 0. 798 Do. 9... N, N -bis(2-methoxyethyl)oleamide 0. 626 Do. 10.. N, N-dibutyloleamide 0. 710 11 N-oleoyl-4-propylpiperidine 0. 847 12.. Morpholide of sel. hydrogenated cottonseed fatty acids. 0. 642 13.. N-methyl-N-butyloleamide 0.607 14.. N-ethoxyethoxyethoxypropyoleamlde. 0. 503 15. N-ethoxyethoxypropyloleamide. 0. 526 16.- N-methoxyisopropyloleamide- 0. 705 17.- N-methoxyethyloleamide 0. 420 18 102 sec paraffin oil N-methoxyethyloleamide. 19 D.0.S Do. 20 N, N-dibnty1-9(10)-carbobutoxyoetadecanamlde-. 0. 610 21 102 sec paraffin oil 0. 818 N, N-dibutyI-9(10) -carbobutoxyoctadecanamide. 22 D.O.S 0.945 Do. 23 N-[9 (10) mercapto- (9) IO-dibutylphosphatostearoyllmorpholine. 0. 615 24 102 sec paraffin oil 0. 552 N-[9(10)mercapto (9)10-dibytu1phos- D.O.S N, N-dibuty1-[9(1 102 sec paraflin 011.

- D.O.S N, N-dibutyl-Q (10)-[dibutylphosphono1stearamid N-ethoxyethoxyethoxypropyl-Q, 10epithiostearami N-ethoxyethoxyethoxypropyl-9(10)mercaptostearamide (9, 1042, IS-diepithiostearoyl) morpholine phatostearoyflmofpholine.

0. 498 N, N-dibutyl-[Q(10)-hydroxy-(9)10- d1]b)uty1phosphato]stearamide.

33-. Bis (2-ethy1hexyl) sebacate 34 100 sec paraffin oil 35 Aero Shell (Mil-7808) 36 Gulf Pride, Single G, MS, multiviscosity.

37 100 sec paraflin oil 0. 813 N, N-dibutyl-Q, 10-12, 13-diepithiostearamide.

38 Bis (Z-ethylhexyl) sebacate 0. 836 Do.

39 100 sec paraflin oil 0. 723 N-9, IO-epithiostearoyl morpholine.

40 Bis(2-ethylhexyl)sebacare 0. 915 Do.

41 100 sec parafiin oil 0.917 N, N-dibutyl-9, lo-dichloi-osteammide.

42 Bis((2-ethylhexyl) sebacate 0.848 Do.

base lubricants in the Shell Four-Ball Wear tests following a modified procedure of ASTM D2266-67. The resulting scar diameter on the balls after running at 600 r.p.m. for 1 hour at 120 C. and kg. load were compared with the scars obtained using commercial lubricants such as Aeroshell Mil-L-70D (di-2-ethylhexyl sebacate and additive), Gulfpride, single G, MS, multiviscosity, and 100 sec. paraffin oil. The results of these tests are reported in Table I.

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

EXAMPLE 19 5 The various amides were evaluated as extreme pressure 7 The performance of the amides tested is given in Tables II, III, and IV.

TABLE II Extreme pressure tests (ASTM D2596-67T) Weld point No With Compound additive 5% #2 1 N,N-bis(2-ethoxyethy1)o1eamide 170 2. N N-di-n-butyl-9,IO-epithiostearamide 300 3.- Ol'eoylrnorpholine 120 4-- N,N-dimethyloleam1de 5...- ,N-di-n-propyloleamide 6. N,N-di-n-hexyloleamide-..- 7.- N,N-dl-n-butylerucamide 8 N,N-di-n-butyl amide of hydrogenated cottonseed fatty acids. N,N-bis(2-methorryethyl)oleamide N-methyl-N-butyloleamide N,N-dibutyl-Q,IO-epithiostearamide. N,SI-dibutyl-Q,10-12,13-diepithiostearam- 1 e. N-ethoxyethoxyethoxypropyloleamide..- N-ethoxyethoxypropyloleamide N-methoxyisopropyloleamide. N-methoxyethyloleamide N-9 IO-epithiostearoylmorphollne- Bist2-ethylhexyDsebacate 100 sec paraflin oil 20 SAE #90 commercial hypoid fluid TABLE III Evaluation of N,N-d1butyl-9,10-12,13-d1-epithlostearamide as an additive and as a base oil in extreme pressure tests.

TABLE IIICoutim1ed Extreme pressure tests on N,N-dibutyl-[9(10)-hydroxy-9(10)-dibutylphosphato1stearamide (P C-No. 7686) (ASTM D259667 '1) v Applieid Avg. Wear 0a scar, Percent Load, s ar, Base 011 Additive gmm. Base oil additive kg. mm.

None 200 0. 887 100 sec parafiin oil (5%) 140 1. 90 No e 300 2. 78 Do (5%) 200 2. None 340 4. 32 -Do (5%) 220 2. 75 None 350 4. .Do (5%) 240 I Weld Non 360 Weld Bis(2-ethylhexyl)sebaeate (5%) 120 l. 51 7686 (5%) 120 2. 28 Do (5%) 180 1. 59 (5%) 140 2. 80 Do (5%) i 190 2. 47 6786 (5%) 50 3. 01 Do (5%) 200 I Weld (5% 160 Weld Do (10%) 240 2.88 7686 (5%) 120 1. 95 Do (10%) 260 3. (5%) 140 2. 85 Do (10%) 270 I Weld 7686 (5%) 150 3. 03 N,N-dibutyl-e,10-12,l3-diepithiostearam- (5%) 160 Weld ide None 120 1. 38

N e 1 0 1, 51 Extreme pressure tests on N-[9(10)-mercapto-9(10)-dibutylphosphato- None 200 1. s9 stearoyflmorpholine (O C-O-No. 7687) None 280 2. 13 None 320 2. 47 None 120 0. 608 None 360 2. None 160 1. 45 None 400 2. 88 None 200 1. 40 None 440 I Weld None 240 1. 70 None 280 7 3. 36

Extreme pressure tests on N ethoxyethoxyethoxypropyl- 9,10-epithiostearamide (PC-O-No. 7682) Extreme pressure tests on N,N-dibutyl-9(10)-earbobuty1oxyoctadeeanamide (PC-O-No. 7688) None 1.92 .22 2-12 one Additive None 120 Weld 123 i: g c p g e e- None 240 2. 35 a 4 g- None 300 2. 19 ggg $832 2&8 iii 30 secondsi None 380 w'eld 5 Test stopped because of extreme decomposition. Did not weld. 7682 2 2 Test stopped because of extreme decomposition and noxious fumes.

(5%) 10 .28 Dunt 1d 7682 (5%) 140 2. 4e 1 we 7682 (5%) 150 Weld 7882 (5%) 120 2. 23 7682 (5%) 140 2. 44 7682 (5%) 150 Weld 35 t N th th 11 l TABLE IV Extreme pressure tes s on -e oxye oxyet oxypropy -9 l0 Evaluation of N-9 IO-eprthlosteeroyl morpholme as an additive and as a mempmteammd" (PC 0 7683) base oil in extreme pressure tests (ASTM D 2596-67T) None 200 1. 54 40 Wear 383: Percent Load, scar, Non8 450 a 1 Base 011 additive kg. mm. i3}; see paraflin oil 5%) 2. oo Do 57) 2 so 7683 (5%) 140 2. 35 7 160 25 7683 (5%) 2. 54 7 180 lw-eld (5%) Weld (579) 80 1 57 7683 (5%) 120 1. 68 7 120 03 7683 (5%) 140 2. 18 7 140 41 (5%) 160 2. 59 (57v) 160 94 7683 (5%) 2. 72 7 00 7683 (5%) 180 Weld (59g) 200 :w e 2 1% one 0 Extreme pressure tests on N-(9,10-12 13-dlepithiostearoyDmoi-pholine 8 g Do None 380 Weld 0118 None 340 z 43 l 10 seconds. 1 5 seconds. 3 50 seconds. None 400 2. 75 None 460 2. 90 None 500 v 2. 9s 55 22%; {33 2-2; We claim 0 Egg (2%) 53 g- 3 1. The compound N (ethoxyethoxyethoxy)propyl- 57 120 9(10) -mercaptostearamide. 2 es .71

5 e ggfi g8 60 References Cited 7 17; 7 wm UNITED 3,746,644 7/1973 Magne et a1. 260-4025 Extreme pressure tests on N,N-dibuty1-9(10)-(dibutylphosphono)stearamide 65 ELBERT L. ROBERTS, Primary Examiner None 120 3.05 None 140 4.50 US. Cl. X.R. None 150 Weld Patent No. 3,801,609 Dated April 2; 1974 Inventcr(s) Frank C. Magne Robert R. Mod, Gene Sum e Ll and w; gfrei Lujarker It is certified that error appears in the above-identified patent and that Letters Patent are hereby corrected as shown below:

Column l, line f -l, change "phosphorous" to phosphorus Column 3, line 17, change "MN-dibutyloleamlde" to N,N-dibutylllnoleamide l ine 35, change "0.75 moles" to 0.73 mole l ine 35 change "0.72 moles" to 0.73 mole I Column l ine-53, change "10 to 10% a Column 6, line 2 change "p.p.m." to RPM line change "ran" to run- Signed and sealed this 21st day of January 1975.

(SEAL) Attest:

McCQY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents