WO2003044136A1

WO2003044136A1 - Multifunctional synthetic lubricant basestocks

Info

Publication number: WO2003044136A1
Application number: PCT/US2002/026694
Authority: WO
Inventors: Halou Oumar-Mahamat; Lowen A. Douglas; Susan C. Ardito
Original assignee: Exxonmobil Chemical Patents Inc.
Priority date: 2001-11-19
Filing date: 2002-08-22
Publication date: 2003-05-30
Also published as: AU2002326727A1

Abstract

The invention describes synthetic lubricant basestocks containing an ester function combined with a carbamate function and/or an amide function. These multifunctional ester fluids may be prepared via condensation of alkanolamines and/or alkylamines with cyclic carbonates and/or lactones followed by reaction with carboxylic acids. Higher viscosity complex multifunctional esters are obtained with polycarboxylic acids or anhydrides and/or polyamines.

Description

MULTIFUNCTIONAL SYNTHETIC LUBRICANT BASESTOCKS

BACKGROUND OF THE INVENTION

(0001) The invention is directed to multifunctional synthetic lubricant basestocks and methods of preparing multifunctional synthetic basestocks. More particularly, the multifunctional basestocks include esters and/or thioesters having carbamate/thiocarbamate and/or amide groups.

(0002) A major concern today is finding methods to reduce engine friction and fuel consumption in internal combustion engines that are safe for the environment and economically attractive. One method is to treat moving parts of such engines with lubricants, preferably biodegradable lubricants with low toxicity.

(0003) The use of alkyldialkanolamides as a minor component in water-based hydraulic fluid compositions is disclosed in U.S. Pat. No. 4,342,658.

(0004) Polyamides esters are disclosed as fuel detergents and/or lubricant dispersants in U.S. Pat. Nos. 5,627,259; 5,628,804 and 5,637,121 and as rheological additives in U.S. Pat. Nos. 4,778,843 and 5,349,011.

(0005) U.S. Pat. No. 5,552,067 discloses the use of dialkylamides as components having increased thermal stability in the absence of oxygen functional fluids.

(0006) The use of carbamates as lubricants is disclosed in U.S. Pat. No. 2,161,615. U.S. Pat No. 4,746,447 teaches the use of cyclic carbonates and their reaction with polyamines to form carbamates useful as lubricant dispersants.

(0007) U.S. Pat. No. 5,863,302, discloses the use of cyclic carbonates and their reaction with amines to form hydroxycarbamates useful as fuel and lubricant friction reducing additives. U.S. Pat. No. 5,126,477 describes carbamates, their production and use as fuel additives.

(0008) There exists a need for synthetic lubricant basestocks with improved volatility and low temperature characteristics, such as low temperature fluidity, particularly as compared to pentaerythritol tetraesters. There exists a need for economical, alternative lubricants for use in functional fluids, such as hydraulic fluids and refrigeration fluids. (0009) There exists a need for synthetic lubricant basestocks that are biodegradable and that may be used in functional fluids that may be intentionally or accidentally discharged into the environment. There exists a need for biodegradable synthetic lubricants for two-cycle engines.

(0010) There exists a need for synthetic lubricant basestocks that promote detergency in a fuel.

SUMMARY OF THE INVENTION

(0011) The instant invention is directed to esters and/or thioesters having carbamate/thiocarbamate and/or amide function generated by reaction of alkanolamines and/or alkylamines with cyclic carbonates, cyclic lactones, cyclic thiocarbonates, cyclic dithiocarbonates, cyclic thiolactones and mixtures thereof to generate hydroxycarbamate, hydroxythiocarbamate, mercaptocarbamate or mercaptothiocarbamate intermediates. These intermediates are further reacted with monocarboxylic acids to generate carbamate polyesters and/or the corresponding sulfur-containing compounds. These carbamate polyesters and corresponding sulfur-containing compounds having esters and carbamates and/or amides have been found to be particularly effective lubricants that are biodegradable and exhibit low toxicity. These compounds may also promote detergency and are economical. Higher viscosity complex multifunctional esters have been obtained when polycarboxylic acids or anhydrides and/or polyamines are used.

(0012) For the sake of convenience, the present invention shall hereafter be discussed in terms of cyclic carbonates and cyclic lactones, generally without further express reference to the corresponding sulfur-containing compounds, i.e., thiolactones, thiocarbonates and dithiocarbonates. Additionally, the carbonyl oxygen in any of the previously mentioned compounds may also be replaced with sulfur. It is understood that the corresponding sulfur-containing compounds are also included within the scope of the invention. DETAILED DESCRIPTION OF THE INVENTION

(0013) In accordance with this invention, there is provided a lubricant composition including a lubricating oil or grease prepared therefrom using the reaction product E produced as shown below in Equations I and II:

(A) (B) (C)

(X-R¹-)₂NCOZ(R²)(R³)Z¹H + n RCOOH — ► (RCOX¹-R¹-)₂NCOZ(R²)(R³)Z¹OCR (II)

(C) (D) (E)

wherein R selected from hydrogen, hydrocarbyl radical, alkenyl radical, and alkyl (C_\ - C₆₀) radical, and optionally containing an aryl, alkaryl, oxygen, sulfur, or nitrogen substituent;

R¹ is selected from a C_\ to C alkylene radical, i.e., (CH )_n where n= 1 to 4 and a Ci to C₄ alkylene radical having an alkyl group substituent, with the proviso that both R¹ groups may not be the same on the amine nitrogen;

R² and R³ are each independently selected from an alkylene radical and an alkylene radical having an alkyl group substituent; R² and R³ may each independently be different from or the same as R¹;

Z and Z¹ are each selected independently from O and S; and

X is selected from OH, SH, and NHY, where Y is selected from hydrogen and an alkyl radical; and

X^I is selected from O, S, and NY, where Y is selected from hydrogen and an alkyl radical; and n = 3.

(0014) Alternatively, X may also be CR4R5R6, where R4, R5 and R6 are each independently selected from hydrogen, a hydrocarbyl radical, alkenyl radical, and an alkyl (CI -C60) radical and which optionally may contain an aryl, alkaryl, oxygen, sulfur, or nitrogen substituent. One embodiment according to this invention in which n = 1 and X is CR4R5R6 provides final products that are carbamate monoesters and have the following general formula: (R⁴R⁵R⁶C-R¹-)₂NCOZ(R )(R³)Z¹OCR (F).

(0015) When compound A has X selected from oxygen and sulfur, primarily the amine nitrogen reacts with the cyclic carbonate or lactone to form, respectively, a carbamate triol/trithiol or amide triol/trithiol under typical reaction conditions (about 40°C to about 100°C and about 1 hour to about 6 hours).

(0016) When X in compound A is a reactive nitrogen (primary or secondary), there is reduced selectivity and one or more of the following intermediate compounds may be formed depending of the stoichiometry of the reactants:

(YHN-R¹-)₂NH + (R^ZCOZ^R³)-*- (YHN-R¹-)₂NCOZ(R²)(R³)Z¹H

(A) (B) (C)

+ [HZ¹(R³)(R²)ZOCNY-R¹-]₂NCOZ(R²)(R³)Z¹H

(«)

+ [HZ¹(R³)(R²)ZOCNY-R¹-](YHN-R¹-)NCOZ(R²)(R³)Z1H

(β)

+ [HZ¹(R³)(R²)ZOCNY-R¹-]₂NH

(γ)

(YHN-R^r-)HN (R¹YN)COZ¹(R³(R²)ZH (δ)

(0017) Compound is the primary intermediate if three moles of cyclic carbonate or lactone are used to react with one mole of the polyamine. sing less carbonate or lactone may result in the possible formation of all five intermediates and some unreacted amine. (0018) Reaction of compound α with carboxylic acid D generates polycarbamate polyesters (when compound B is a carbonate) or polyamide polyesters (when compound B is a lactone).

(0019) The ratio of the amine may be adjusted to the amount of the carbonate or lactone used in order to generate primarily one compound or mixture of compounds C, α, β, γ and δ.

(0020) In another embodiment according to the present invention, only one of the amine substituents contains an ester-generating group. One embodiment, in which n = 2, provides final products that are carbamate diesters having the general formula:

(RCOX¹-R¹-)(R⁴R⁵R⁶C-R¹-)NCOZ(R²)(R³)Z¹OCR (G),

wherein R, R¹, R², R³, R⁴, R⁵, R⁶, X¹, Z and Z¹ are as described above.

(0021 ) The present invention also includes a method of preparing carbamate polyester E, as shown in Equations I and II. An amine A and a cyclic carbonate B are mixed under conditions sufficient to cause a reaction to form hydroxycarbamate intermediate C as shown in Equation I. An acid D and, optionally a catalyst, is added to the hydroxycarbamate intermediate C to generate the polyester carbamate E product, which results from esterifϊcation of the hydroxycarbamate intermediate C and acid D, as shown in Equation II when XI = O. A thioester group is formed when XI = S and an amide group is formed when XI = NY. The hydroxycarbamate intermediate C, or sulfur and amine analogs, may be isolated and purified prior to subsequent reaction with a carboxylic acid D. An anhydride may be used in place of the acid D. Although subsequent discussion shall be in terms of an acid D, it is understood that the term acid shall also include anhydrides, esters, acid chlorides and equivalents thereof. Alternatively, the hydroxycarbamates C may be treated with carboxylic acids D without prior isolation or purification to form the polyester carbamate E. (0022) The present invention also includes a method of preparing amide esters M, N and O by reacting amine A with lactone K to form the intermediate L. See Equations VI, VII, VIII and IX, infra. The intermediate L is treated with acid D to form the product M, N or O, depending on the nature of amine A. The method is similar to that described above for cyclic carbonates.

(0023) The reaction steps may be performed in any solvent that provides at least sufficient partial solubility of the reactants to permit the formation of the desired products. In this context, solvent refers to a material other than one of the reactants or products. The reaction may also be conducted in the absence of a solvent when at least one of the reactants is a liquid in which the other reactants have sufficient solubility to allow formation of the desired products. Alternatively, the reaction may also be conducted in the absence of a solvent when at least one of the reactants has a melting point low enough to permit melting of the reactant and has sufficient ability to dissolve the other reactants to permit formation of the desired products.

(0024) The reactions may be performed as batch, semi-batch or continuous operations. The reactions may be conducted in any conventional reactors. One of ordinary skill in the art can select appropriate reactors and can also select appropriate conditions for batch, semi-batch, and continuous operations.

(0025) Stoichiometric quantities of amines, cyclic carbonates and acids are preferred. However, an excess of one of the reagents may be suitable. The ratio of amine to cyclic carbonate or amine to lactone may range from about 10:1 to about 1:10.

(0026) Suitable alkylene carbonates B include, but are not limited to, cyclic ethylene carbonate and propylene carbonate. Mixtures of alkylene carbonates may also be used. The corresponding monothio-, dithio- and trithiocarbonates may also be used. The molar ratio of amine to carbonate or lactone is chosen to provide the desired ratio of intermediate compounds, which are then treated with acid D. (0027) When cyclic carbonates are used in less than stoichiometric quantities, i.e., when excess amine is present, mixtures of carbamate esters and amide esters are obtained. The amine to carbonate ratio may range from about 1:10 to about 10:1. The amine to carbonate ratio is typically more than or equal to about 1. An excess of amine may be used provided that reaction time and temperature are selected to reduce or minimize, or preferably to prevent, reaction of two molar equivalents of amine with one molar equivalent of carbonate which would result in a urea by-product and a glycol by-product. Generally, reaction conditions used to form intermediate C do not lead to the formation of such urea and gylcol byproducts even in the presence of a large excess of amine A. Any excess unreacted amine may be recovered by conventional methods.

(0028) The molar ratio of amine to lactone is typically from about 1:10 to about 10:1. However, a large molar excess of amine to lactone may be used since the intermediate hydroxycarbamate L, formed from reaction of the amine and the lactone, will not undergo further reaction to form urea or glycol by-products.

(0029) The reaction of amine A with a cyclic carbonate B results in the formation of a hydroxyl group, in addition to a carbamate group, in intermediate C. The molar ratio of acid D to the hydroxyl group formed in intermediate C is typically about 1:1. An excess of acid D may be used with the unreacted excess acid D being recovered by conventionalethods.

(0030) Intermediate C may have multiple heteroatoms, i.e.,oxygen, nitrogen and sulfur, capable of reaction with the acid D. The molar ratio of acid D to intermediate C may be adjusted on a molar basis to permit complete or partial reaction of the heteroatoms with acid D to form esters, amides or thioesters, respectively. For example, when X = OH, then carbamate triesters, carbamate diesters and/or carbamate monoesters may be made.

(0031 ) Amides and/or amide esters may be made directly, by reaction of amine A with acid D, having one less ester group than would be present in reaction product of intermediate C, made by the reaction of amine A with cyclic carbonate B, followed by reaction of C with an acid D. For applications in which an amide ester is desirable, amines and carboxylic acids react to generate amide ester fluids, which generally have higher viscosities and sometimes are more economical than corresponding carbamate esters.

(0032) Amide diesters, amide monoesters, and/or amides are made by reacting the amine A, in which X=OH, with excess carboxylic acid D. The products may be a single compound or a mixture of compounds. The reaction product may include compounds of one or all of the following formulae depending on the nature of the amines used:

(X-R¹-)₂ H + nRCOOH — ► (n = 3) (RCOX^R^NCOR (III)

(A) (D) (H)

— ► (n = l) (R^ C-R^NCOR (IV)

(I)

— ► (n = 2)(RCOX¹-R¹-)(R⁴R⁵R⁶C-R¹-)NCOR. (V)

(J)

X = OH, R⁴R⁵R⁶C, X¹ = O where X and X¹

are as defined above. The corresponding sulfur and nitrogen compounds may be prepared where X = SH or NHY, wherein Y is defined as above, and X¹ = S or NY, respectively.

(0033) Similar amide function containing products can be obtained by using cyclic lactones in place of carbonates. Generally amide monoesters, amide diesters, and amide triesters result from the reaction described below when Z ≠ Zl and Z = CR7R8:

(X-R^J-)₂NH + (R²)CR⁷ R^OZ^R³) — ► (X-R¹-)₂NCOCR⁷R⁸(R²) (R³) Z1H (VI)

(A) (K) (L)

(X-R^NCOCRV (R²)(R³)Z1H + nRCOOH — ►

(L) (D) n = 3 (RCOX¹-R¹-)₂NCOCR⁷R⁸ (R²)(R³)Z¹OCR (VII)

(M) n = l (R⁴R⁵C-R¹-)₂NCOCR⁷R⁸ (R²)(R³)Z¹OCR (VIII)

(N) n = 2 (RCOX¹-R¹-)(R⁴R⁵R⁶C-R¹-)NCOCR⁷R⁸(R²)(R³)Z¹OCR

(TX)

(O)

(0034) X, XI, Zl, R, Rl, R2, R3, R4, R5 and R6 are as defined above. R7 and R8 are each independently hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (CI - C60) radical and optionally containing one or more of an aryl, alkaryl, oxygen, sulfur or nitrogen substituent.

(0035) In all cases described above, multifunctional carboxylic acids and/or carboxylic anhydrides may be used as substitutes for part or all of the monocarboxylic acids to generate higher viscosity complex mixtures containing polycarbamate polyesters and/or polyamide polyesters in addition to the compounds described above. Suitable multifuctional carboxylic acids include, but are not limited to, adipic acid, succinic acid, maleic acid, azelaic acid, sebacic acid, malonic acid, malic acid, citric acid, phthalic acid, trimellitic acid, pyromellitic acid and the like. Multifunctional anhydrides include, but are not limited to, adipic anhydride, succinic anhydride, maleic anhydride, azelaic anhydride, sebacic anhydride, malonic anhydride, malic anhydride, citric anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride and the like.

(0036) Temperatures between about 25°C and about 350°C with reaction times of from about 1 hours to about 36 hours are generally applied. The preferred temperatures for the intermediate reactions between the amines and the cyclic carbonates and/or lactones are between from about 40°C and about 100°C with corresponding preferred times between from about 1 hour to about 6 hours. Temperatures between 160°C and 225 °C and times between 6 hours and 24 hours are preferred for the reactions of esterification of the intermediates and amidations of carboxylic acids. (0037) Suitable esterification catalysts include, but are not limited to, inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and acidified clays; and organic acids such as methane sulfonic acid, benzenesulfonic acid, toluene sulfonic acid, and acidic resins. Other suitable esterification catalysts include, but are not limited to, alkali metal alkoxides such as sodium aluminate/alumina; zinc or manganese acetates; and organometallics such as organo-tin or organo- titanates.

(0038) Suitable amines include, but are not limited to, alkylamines; cycloaklamines; arylamines; etheramines; dialkylamines such as dimethylamine, diethylamine, and di(2-ethylhexyl)amine; dicycloalkylamines; diarylamines; alkyl(hydroxyalkyl)amines; dietheramines; di(hydroxyalkyl)amines such as diethanolamine, and diisopropanolamine; cyclic amines such as pyrrolidine, piperidine, homopiperidine, morpholine, and thiomorpholine; cyclic diamines such as piperazine, homopiperazine; polyamines such as ethylenediamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentamine and polyethylene amine; other diamines having sufficient reactivity to react with a cyclic carbonate or cyclic lactone; and mixtures thereof.

(0039) Suitable cyclic carbonates include, but are not limited to, alkylene carbonates such as ethylene carbonate and propylene carbonate; thioalkylene carbonates such as ethylene trithiocarbonate; and mixtures thereof. Other suitable compounds include, but are not limited to, cyclic lactones such as β-lactones, γ- lactones, δ-lactones and mixtures thereof. Mixtures of one or more cyclic carbonates with one or more cyclic lactones may also be used. The corresponding monothio-, dithio- and trithiocarbonates are also suitable.

Example 1:

(0040) Diethanolamine (270 grams, 2.6 moles) and propylene carbonate (258 grams, 2.5 moles) were heated at 80°C for 2 hours under a nitrogen atmosphere. Sodium aluminate/alumina (0.5g/1.0g) was added as a catalyst. Heptanoic acid (365 grams, 2.8 moles) and octanoic/decanoic acid mixture (774 grams, 5.0 moles) were added. The octanoic/decanoic acid mixture is about 60 weight % octanoic acid and about 40 weight % decanoic acid. The reaction mixture was heated at 185°C. The water formed during the reaction was constantly removed by distillation using a Dean-Stark apparatus. The reaction was stopped after 14 hours, when titration showed an acid number of about 0. The reaction mixture was then filtered through Celite® to obtain about 1500 grams of clear slightly yellow liquid.

(0041 ) The reaction procedure of Example 1 is typical of the procedures used to make representative fluids such as the examples presented below. Physical characteristics for diethanolamine derivatives are listed in Table I and for other amine derivatives in Table 2. Table 2 contains test results showing that some of these compounds may be suitable for use as refrigeration fluids due to their compatibility with the polar refrigerant R-134a. Derivatives of diethanolamine, however, demonstrated poor wear protection and incompatibility with some of the material encountered in the refrigeration machines such as polyethyleneterephthalate (PET). The incompatibility with PET is shown by immersion test ASHRAE 86. The test method is provided by the American Society of Heating, Refrigeration and Air-conditioning Engineers.

Table 1

Carbamate Polyesters from Diethanolamine Physical Properties

EC = Ethylene Carbonate; PC = Propylene Carbonate; KV ₀c ⁼ Kinematic Viscosity @ 40°C; VI = Viscosity Index; D = Density @ 15.6°C; PP = Pour Point; FP = Flash Point.

Table 2

Carbamate Esters as Refrigeration Fluids R-134a Low Temperature Miscibility and Wear Protection Properties

EC = Ethylene Carbonate; PC = Propylene Carbonate;

ASHRAE = American Society of Heating, Refrigeration and Air-conditioning Engineers.

Example 2:

(0042) This reaction was conducted in a manner similar to Example 1, using 421 grams (4 moles) of diethanolamine, 301 grams (3 moles) of propylene carbonate, 912 grams (5.9 moles) of octanoic/decanoic acid mixture, 1665 grams (5.9 moles) of oleic acid, and 0.66 gram of alumina and 1.3 grams of sodium aluminate as catalyst. In addition to the Celite® used in Example 1, calcium carbonate was added to the filter bed before filtration of the final product to remove residual unreacted acid .2845 grams of clear brown liquid was obtained.

(0043) The product of this example is a mixture of carbamate polyesters and amide polyesters designed to obtain an improved, or preferably an optimum, viscosity for use as two-cycle engine lubricant basestock. The fluid was then mixed with three additive packages and tested for both air-cooled and water- cooled two-cycle engine applications. The physical characteristics of the base fluid and the three formulations are presented in Table 3 and the test results in Table 4.

Table 3

Mixture of Carbamate Polyesters and Amide Polyesters

For Two-Cycle Engine Applications

Physical Properties

CEC = Coordinating European ounc .

Table 4

Mixture of Carbamate Polyesters and Amide Polyesters

For Two-Cycle Engine Applications

Test Results

= Japanese Automo e Stan ard Organization; CEC = Coordinating European Council; NMMA = National Marine Manufacturers Association

Example 3:

(0044) This reaction was conducted similarly to Example 2, using only diethanolamine and carboxylic acids, in a 1:3 molar ratio, to generate amide diesters. The physical properties of the products from this reaction were compared to those of products obtained using pentaerythritol and the same carboxylic acids (see Table 5). Also presented in Table 6 are biodegradability and fish toxicity test results for amide diesters and higher viscosity complex polyamide polyesters. The complex polyamide polyesters were made similarly by replacing some of the monocarboxylic acids by dicarboxylic acids or anhydrides. Approximately, 0.5 moles of dicarboxylic acid or anhydride was substituted for 1 mole of monocarboxylic acid.

Table 5

Monoamide Diesters vs. Pentaerythritol Tetraesters

Complex Polyamide Polyesters

Physical Properties

= et anolamine; PE = Pentaeryt r tol; DDSA = Dodecenylsuccinic anhydride; KV = Kinematic Viscosity.

Table 6

Environmental Properties of Amide Esters from Diethanolamine

DDSA = Dodecenylsuccinic anhydride; OECD = Organization for Economic Cooperation and Development; CEC = Coordinating European Council

(0045) The invention having now been fully described, it should be understood that it may be embodied in other .specific forms or variations without departing from its spirit or essential characteristics. Additionally, the compositions E, G, H, I, J, K, O, P, and Q may be used as additives in lubricant compositions. When composition E, G, H, I, J, K, O, P and Q are used additives, the additives may be used in amounts ranging from about 0.5 wt% to about 45 wt%, preferably from about 1 wt% to about 30 wt%, and more preferably from about 5 wt% to about 20 wt% based on the weight of the basestock material. The additive compositions may be used in conunction with basestock materials including, but not limited to, poly-alpha-olefins (PAO), mineral oils and mixture thereof. The additive compositions E, G, H, I, J, K, O, P, and Q may be used singly or in combination as additives to a basestock. The additive compositions may also be used singly or in combination, in amounts effective to function as detergents. Accordingly, the embodiments described above are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Claims

CLAIMSWe claim:

1. A synthetic lubricant basestock comprising a reaction product obtained by reacting:

(a) an amine having a formula: (X-R¹-)₂NH;

(b) a cyclic compound having a formula: (R^ZCOZ^R³); and

(c) an acid having the formula: RCOOH, wherein each X is selected from OH, SH, NHY and CR⁴R⁵R⁶, wherein

R¹ is selected from a Cj to C₄ alkylene radical and a to C₄ alkylene radical having an alkyl group substituent, with the proviso that both R¹ groups may not be the same;

R² and R³ are selected independently from an alkene and an alkene having an alkyl group substituent;

Z and Z¹ are each selected independently from O, S and CR⁷R⁸ with the proviso that both Z and Z¹ are not CR⁷R⁸;

R, R⁴, R⁵, R⁶, R⁷ and R⁸ are each selected independently from hydrogen, a hydrocarbyl radical, alkenyl radical, and an alkyl (Ci - C₆₀) radical; and

Y is selected from hydrogen and the alkyl ( -Ceo) radical.

2. The basestock of Claim 1 , wherein the cyclic compound is selected propylene carbonate and ethylene carbonate.

3. The basestock of Claim 1, wherein the acid is selected from adipic acid, pentanoic acid, heptanoic acid, octanoic acid, decanoic acid, iso-octadecanoic acid, oleic acid, 2 ethylhexanoic acid, nonanoic acid, isononanoic acid, iso- octanoic acid and mixtures thereof.

4. The basestock of Claim 1, wherein at least one of R² and R³ is different

5. A synthetic lubricant basestock comprising: a compound having the formula: (RCOX^R^NCOZ ^XR^Z'OCR, wherein

R is selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (Cj - C₆₀) radical;

R¹ is selected from a Cj to C₄ alkylene radical and a Cj to C₄ alkylene radical having an alkyl group substituent, with the proviso that both R¹ groups may not be the same;

R and R are each selected independently from an alkylene radical or alkylene having an alkyl group substituent;

Z is selected from O, S and CR⁷R^S, wherein R⁷ and R⁸ are each independently selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (Ci_. - C₆₀) radical;

Z¹ is selected from O and S; and

X¹ is selected from O, S and NY, wherein Y is selected from hydrogen and alkyl.

6. The basestock of Claim 5, wherein Z and Z¹ are oxygen.

7. The basestock of Claim 5, wherein Z is CR⁷R⁸.

8. A synthetic lubricant basestock comprising: a compound having a formula:

(RCOX¹-R¹-)₂NCOZ(R²)(R³)Z¹OCR, wherein the compound having the formula (RCOX¹-R¹-)₂NCOZ(R²)(R³)Z¹OCR is obtained by reacting:

(a) an amine having a formula: (X-R¹-)₃NH;

(b) a cyclic compound having a formula: (R^ZCOZ^R³); and

(c) an acid having a formula: RCOOH, wherein

R is selected from hydrogen, hydrocarbyl, alkenyl, and alkyl (Ci_. - C₆o);

R¹ is selected from a d to C₄ alkyl radical or a Cj to C₄ alkyl radical having an alkyl group substituent, with the proviso that both R¹ groups may not be the same;

R and R are each selected independently from an alkylene radical and alkylene radical having an alkyl group substituent;

Z is selected from O, S and CR⁷R⁸, wherein R⁷ and R⁸ are each independently selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (C_Ϊ - C₆₀) radical;

Z¹ is selected from O and S; each X is selected independently from OH, SH, and NHY, where Y is selected from hydrogen and alkyl; each X¹ is selected independently from O, S, and NY, wherein Y is selected from hydrogen and alkyl; and the molar ratio of the acid to the amine is about 3.

9. The lubricant basestock of Claim 8, wherein the cyclic compound is selected from propylene carbonate and ethylene carbonate.

10. The lubricant basestock of Claim 8, wherein the acid is selected from adipic acid, pentanoic acid, heptanoic acid, octanoic acid, decanoic acid, iso- octadecanoic acid, oleic acid, 2 ethylhexanoic acid, nonanoic acid, isononanoic acid, iso-octanoic acid and mixtures thereof.

11. The lubricant basestock of Claim 8, wherein at least one of R² and R³ is different from R¹.

12. A synthetic lubricant basestock comprising a reaction product obtained by reacting:

(a) an amine having a formula: (X-R^!-)₂NH; and

(b) an acid having a formula: RCOOH; wherein each X is independently selected from OH, SH, CR⁴R⁵R⁶, and NHY, wherein Y is selected from hydrogen and alkyl;

R, R⁴, R⁵ and R⁶ are each independently selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl ( - C₆₀) radical;

R¹ is selected from a d to C₄ alkylene radical and a Cj to C₄ alkylene radical having an alkyl substituent, with the proviso that both R¹ groups may not be the same; and the molar ratio of the acid to the amine ranges from about 1 to about 3.

13. The lubricant basestock of Claim 12, wherein the molar ratio of the acid to the amine is about 1.

14. The lubricant basestock of Claim 12, wherein the molar ratio of the acid to the amine is about 2.

15. The lubricant basestock of Claim 12, wherein the molar ratio of the acid to" the amine is about 3.

16. The lubricant basestock of Claim 12, wherein the acid is selected from adipic acid, pentanoic acid, heptanoic acid, octanoic acid, decanoic acid, iso- octadecanoic acid, oleic acid, 2 ethylhexanoic acid, nonanoic acid, isononanoic acid, iso-octanoic acid and mixtures thereof.

17. A synthetic lubricant basestock comprising: (a) a compound of the formula:

(RCOX'-R^NCOR, wherein

X¹ is independently selected from O, S, and NY, wherein Y is selected from hydrogen and alkyl;

R is selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (Ci - C₆₀) radical;

R¹ is selected from a Cj to C₄ alkylene radical and a Ci to C₄ alkylene radical having an alkyl substituent, with the proviso that both R¹ groups may not be the same.

18. The lubricant basetock of Claim 17, wherein the acid is selected from adipic acid, pentanoic acid, heptanoic acid, octanoic acid, decanoic acid, iso- octadecanoic acid, oleic acid, 2 ethylhexanoic acid, nonanoic acid, isononanoic acid, iso-octanoic acid and mixtures thereof.

19. A lubricant composition comprising: a basestock selected from a mineral oil and a poly-alpha-olefins; and a reaction product obtained by reacting:

(a) an amine having a formula: (X-R¹-)₂NH;

(b) a cyclic compound having a formula: (R^ZCOZ^R³); and

R¹ is selected from a d to C₄ alkylene radical and a d to C₄ alkylene radical having an alkyl group substituent, with the proviso that both R¹ groups may not be the same;

R² and R³ are selected independently from an alkylene radical and an alkylene radical having an alkyl group substituent;

R, R⁴, R⁵, R⁶, R⁷ and R⁸ are each selected independently from hydrogen, a hydrocarbyl radical, alkenyl radical, and an alkyl (Cj - C₆₀) radical;

Z and Z¹ are each selected independently from O, S and CR⁷R⁸ with the proviso that both Z and Z¹ are not CR⁷R⁸; and

Y is selected from hydrogen and the alkyl (d-C₆o) radical.

20. A lubricant composition comprising: a basestock selected from a mineral oil and a poly-alpha-olefins; and a reaction product having a formula: (RCOX¹-R¹-)₂NCOZ(R²)(R³)Z¹OCR, wherein

R is selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (d - C₆₀) radical; R¹ is selected from a Ci to C alkylene radical and a d to C₄ alkylene radical having an alkyl group substituent, with the proviso that both R¹ groups may not be the same;

R and R are each selected independently from an alkylene radical or alkylene radical having an alkyl group substituent;

Z is selected from O, S and CR⁷R⁸, wherein R⁷ and R⁸ are each independently selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (d - C₆₀) radical;

Z¹ is selected from O and S;

X is selected from OH, SH and NHY, wherein Y is selected from hydrogen and alkyl; and

X^I is selected from O, S and NY, wherein Y is selected from hydrogen and alkyl.

21. A lubricant composition comprising: a basestock selected from a mineral oil and a poly-alpha-olefins; and a reaction product obtain by reacting:

(a) an amine having a formula: (X-R^!-)₂NH; and

R, R⁴, R⁵ and R⁶ are each independently selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (d - C₆₀) radical; R¹ is selected from a d to C alkylene radical and a Ci to C₄ alkylene radical having an alkyl substituent, with the proviso that both R¹ groups may not be the same; and the molar ratio of the acid to the amine ranges from about 1 to about 3.

22. A lubricant composition comprising: a basestock selected from a mineral oil and a poly-alpha-olefins; and (a) a compound of the formula:

(RCOX^R^NCOR, wherein

R is selected from hydrogen, a hydrocarbyl radical, an alkenyl radical, and an alkyl (d - C₆₀) radical;

R¹ is selected from a Cj to C₄ alkylene radical and a Ci to C alkylene radical having an alkyl substituent, with the proviso that both R¹ groups may not be the same; and the molar ratio of the acid to the amine ranges from about 1 to about 3.