DE2126451A1 - Organic substances containing oxidation inhibitors, in particular fuels or fuels and lubricants - Google Patents

Description

SHELL INTERlTAiDIOIiALE RESEARCH IiAATSGHAPPIJ, N.Y .., The Hague, Netherlands

¹¹ organic substances containing oxidation inhibitors, in particular fuels or fuels and lubricants "

Priority: May 29, 1970, Great Britain, No. 25 992/70

The invention relates to organic substances, in particular Fuels or fuels and lubricants that are stabilized against oxidative degradation by means of oxidation inhibitors are.

Numerous organic substances are known to be susceptible to oxidative degradation. Organic liquids such as lubricants , substances and fuels or fuels, which are often exposed to severe operating conditions, such as elevated temperatures, are particularly susceptible to oxidation. It is also known to inhibit this susceptibility to oxidation of organic substances by incorporating oxidation inhibitors. Numerous such oxidation inhibitors are known, but their effectiveness is often limited under certain operating conditions. Some of these oxidation inhibitors can be used, for example, at the lower working temperatures, for example below 100 ^° C., but lose at higher temperatures

109849 / U1 1

ren, as above 100 G and even more so above 200 C, their sufficient effectiveness.

The numerous antioxidants proposed so far are compounds with a wide variety of molecular structures. To a limited extent, they are also suitable as oxidation inhibitors boron-containing compounds.

By replacing a G atora with a nitrogen atom in an aromatic system, an isoconjugated positive ion is formed, e.g. the pyridinium ion (CcNHg). Analogously, it would be expected that by replacing a carbon atom with a boron atom, an isoconjugated negative ion, such as an ion of the formula C ₁ -BIL - "", would be obtained. However, compounds of this type are not known. However, the replacement of two adjacent carbon atoms in an aromatic system by a nitrogen atom and a boron atom leads to the formation of a neutral system with an aromatic character; see MJ-S. Dewar, Journal of the Chemical Society, (1958), page 3075 ff. There are also known the production and properties of heteroaromatic compounds in the molecule of which two adjacent carbon atoms are replaced by a nitrogen and a boron atom, as well as analogous systems, in which the neighboring carbon atoms have been replaced by a boron and an oxygen atom, a boron and a sulfur atom or a boron and a phosphorus atom; See MJS Dewar, "Progress in Boron Chemistry" (1964), Volume 1, page 235 ff (Verlag H. Steinberg, published by Pergamon Press). The nomenclature of these heteroaromatic compounds was and has been discussed in the Journal of the Chemical Society (1959), page 2728

1098A9 / U1 1

obviously generally enforced that the second prefix "aro" between the first prefix and the name of the cyclic hydrocarbon with which the compound is isoconjugated, inserted v / ground. This nomenclature will too hereinafter applied, the term "borazaro compound" a compound means which one in its molecular structure Boron atom and one nitrogen atom, which atoms replace two adjacent carbon atoms in an aromatic system. One such borazaro compound is with the corresponding aromatic compound which has no such nitrogen and boron atom contains, isoconjugated. The last-mentioned aromatic system can be a carbocyclic system, or heteroatoms, e.g. nitrogen, oxygen or sulfur atoms.

The object of the invention was to provide novel oxidation inhibitors To provide organic substances, in particular fuels or fuels and lubricants, their resistance to oxidation extends to a wide variety of operating conditions. This problem is solved by the invention

The invention thus relates to oxidation inhibitors organic substances, in particular fuels or fuels and lubricants, which are characterized by that they

(A) at least one borazaro compound and optionally additionally

(h) at least one conventional oxidation monitor *

Surprisingly, it has been found that in the inventive Borazaro compounds containing organic substances, which have a nitrogen and a boron atom in an adjacent position in an aromatic ring system, these substances, in particular organic liquids suitable as fuels or fuels or lubricants, particularly high resistance to oxidation to lend.

The borazaro compounds are in the organic compounds according to the invention Substances preferably dissolved or thoroughly dispersed.

The borazaro compounds (a) preferably have one of the general ones Formulas I to V

\ B-R '

(R " ¹ )

(D

(in)

10-9849 / U 1 1

(V)

in which R is a hydrogen atom or a hydrocarbon radical, the radicals R ¹ , R "and R" ^{1 are} identical or different and halogen atoms, hydroxyl groups, optionally halogenated oxyhydrocarbyl radicals or optionally halogenated hydrocarbon radicals, preferably aliphatic ^ or cycloaliphatic hydrocarbon radicals, aryl or Aralkyl radicals, where the radicals R and R " ^{1 taken} together can also form a cyclic structure, χ has the value 0 or an integer from 1 to 4, y is 0, 1 or 2, s is 0 or 1 and the radicals X each represent an atomic group such that two adjacent radicals X taken together form a radical

- Jf t Rim R.

form and the remaining radicals X are carbon, nitrogen, oxygen or sulfur atoms or another remainder

- B. - ii R "" R.

109849 / U11

where R " ^{lf is} a halogen atom, a hydroxyl group, an optionally halogenated hydrocarbon radical, an optionally halogenated oxyhydroearbyl radical or a bridging oxygen atom to a boron atom, a borazaro compound, and v / obei in the formulas I to Y very generally one or several of the carbon atoms of any aromatic ring can be replaced by nitrogen, oxygen, Sehivefel or boron atom (s).

The aforementioned borazaro compounds can be used within the scope of the invention added to a wide variety of solid and liquid organic substances to reduce their susceptibility to oxidation are examples of such substances susceptible to oxidation organic polymers such as elastomers. The aforementioned Borazaro connect however, they are particularly suitable as additives for lubricating oils or liquid hydrocarbon fuels or fuels. The base lubricating oils can be mineral lubricating oils or synthetic organic lubricating oils. The ones described above Borazaro compounds, however, are particularly effective as additives for synthetic organic lubricating oils. The lubricating oils are not only used for pure lubricating purposes, but they are also suitable as liquids with a specific function, e.g. as hydraulic oils, v / ie oils for automatic Gearboxes or brake fluids, or as components for metalworking oils, such as cutting or machine oils. The effectiveness the borazaro compounds (a) as oxidation inhibitors is generally dependent on the respective organic base component, which these compounds (individually or in the form of mixtures) are incorporated, the respective boraza

109849 / U1 1

crude compound (s) and the concentration used in each case of these connections. Put in view of their high effectiveness the borazaro compounds (a) are particularly valuable oxidation inhibitors for synthetic organic oils when they are used extremely harsh conditions that promote oxidative degradation occur, especially for oils intended for use as lubricants at elevated operating temperatures, as in Plug-in type gas turbine engines are provided. One special

Ester oils. Borazaro compounds have a good effect for synthetic / BeIu]) IeIe for liquid fuels or fuels to which the borazaro compounds may be incorporated, oii ^ a petrol, kerosene and heating oils. '

Borazaro compounds preferred as additives for the organic substances according to the invention are the 10,9-borazarophenanthrene compounds of the general formula III, where the radicals R '"are in particular halogenators, unbranched or branched alkyl radicals containing up to 20 carbon atoms (for example methyl, ethyl, propyl -, isopropyl, octyl, decyl or monadecyl groups), cycloaliphatic radicals (eg cyclohexyl groups) i aryl radicals (eg phenyl groups), alkaryl radicals (eg. Lolyl or phenyloctyl groups), oxyhydrocarbyl radicals, which in turn are oxyalkyl, oxycycloalkyl - or oxyalkaryl radicals, or halogenated hydrocarbon or oxyhydrocarbyl radicals. Particularly preferred according to the invention are the borazaro compounds of the general formula IY in which the radicals R " ^{1 have} the meaning given above for the compounds of the formula III.

Examples of borazaro compounds in the molecule of which the radical R forms a cyclic structure with a radical R "· are

109849 / U11

Compounds of the general formula VI

in which R "'has the meaning given above (formula III and IV) and a is 0, 1, 2 or 3 .

Examples of borazaro compounds, which in the same ring, on whose structure a radical

_B - H-I!

R ¹ R
involved, have another heteroatom, are Borasaro-

isoquinoline and its derivatives with the general formula VII

(VII)

in which R, R ¹ , R ", R"', χ and ζ have the meanings given above in the case of the general formulas I to V.

Although the theoretical basis of the mode of action of the borazaro compounds (a) is not completely cleared up in the organic substances according to the invention, it is assumed that the surprising favorable properties of the borazaro compounds as oxidation inhibitors compared to other organoboron compounds

1098A9 / U1 1

bonds are due to the presence of the -NB- group in the molecular structure of these compounds. It is considered important that the borazaro compound (s) should be in solution in the organic substance to be stabilized, and that the term "thoroughly dispersed" here refers to the analogous state when the organic base substance is solid, eg a hollow polymer , is, 3s it is not ruled out that at least some of the boraisaro compounds (a) are subject to a certain form of transformation of the molecular structure when they dissolve in the organic substance to be stabilized, although it is assumed that the presence of the group -HB- conditional properties are retained.

It is also assumed that the extraordinarily high effectiveness the Borasaro compounds used according to the invention as oxidation inhibitors in synthetic lubricants and Hydraulic oils are due to the ability of these compounds to dissolve in these fluids in such a form to be present that they are oxygen, which otherwise: at elevated temperatures an unacceptable high degree of oxidative Would cause degradation, bind particularly well or remove in some other way. In this respect alone, the invention bring used borazaro compounds a great and unexpected technical advance in the field of heavy-duty synthetic lubricants with them.

The borazaro compounds used according to the invention can be prepared by any known method, such as by photocyclization

1098A9 / U11

tion of iodaniline phenoxyboranes. Good LR results are achieved when a suitable Auin with a boron trihalide, v / ie boron trichloride, in a solvent, e.g. Xylene, refluxed and the product obtained by adding an anhydrous aluminum halide (e.g. AlCl.,) And subsequent further boiling under reflux is celiated. The halogen atom on the halide obtained is then converted into the desired substituent by means of a further reaction replaced. By reacting the halide with water, for example, the corresponding hydroxy compound can be prepared from which the Ether can be obtained. By implementation with a Grignard connection an alkyl derivative is obtained, while the reaction with an alcohol leads to an alkoxy derivative. It should be noted, however, that within the scope of the invention, any suitable or known processes for the production of the Borazaroverbin ™ compounds (a) can be applied.

The preparation of a borazo ether suitable according to the invention according to the method described above will now be explained.

Production of BJs- (IO, 9-borazarophenanthryl) ~ ether In a solution of 300 g of 2-aminobiphenyl in 2.2 liters of anhydrous xylene, which is in a stirrer (sealed stirrer guide), thermometer, reflux condenser with calcium chloride protective tube and pressure-balanced 500 ml dropping funnel equipped 5 liter four-necked flask is presented, a solution of 300 g of boron trichloride in 300 ml of cold anhydrous xylene is added dropwise within 30 minutes with stirring. The one at first

109849/14 11

formed v / icy lodite beat dissolves again later, and a clear, amber-colored solution is obtained. This solution is refluxed for 1 hour, v / oboi Chlorv.'asserst off and uioiit-reversed boron chloride escape, Hach dem When it is cooled to 100 ° C., 15 g of powdered anhydrous are obtained

AlCl-z entered, and refluxing is continued for a further 2 hours. The solution is then cooled again to 100 ° C. and an additional 5 g of aluminum chloride are added. The resulting mixture is refluxed for a further 20 hours
cooked. Then the reflux condenser is replaced by a distillation attachment and a certain amount of solvent is used
(1.7 liters) distilled off with thorough stirring. The resulting solution is then cooled and carefully added to 2.5 liters
Water added. Caution is necessary because the reaction is very stormy at the beginning. During the addition of water, a solid substance separates out in the reaction mixture
which is filtered off and dried at room temperature. After recrystallization from Ilethylcyclohexane (2 percent solution)
in the presence of activated charcoal, 165 g are obtained (yield =
50 percent) of a creamy white powder with a melting point of 166

up to 168 C • * 5 B. 7th N Analysis: ber .: 5 , 9 7th , 5 found: , 7 , 4.

The following compounds represent specific examples of oxidation inhibitors which can be used in the context of the invention Co-oxidation inhibitors, which are oxidation-prone organic Substances can be added:

109849 / U11

BIs- (IO, 9-borazarophenanthryl) ether 10-benzyl-10,9-borazarophenanthrene 10-iithoxy-10, 9-borazarophenanthrene 10-Ethy1-10,9-borazarophenanthrene Bis (9-ethy1-10,9-borazarophenanthryl) ether Bis ~ (4,3 ~ borazaro-4-isoquinolyl) -ether bis- (2, l-borazarona / phthyl) -ether.

It depends untei "including the nature of the organic base component, the conditions of normal use of this material as well as the presence or absence wei ^ e" -? ^"One additives, for example from other oxidation inhibitors, from, v / hich shares of Borazaroverbindungen ( a) are necessary for the stabilization of a certain organic substance against the oxidative degradation to such a degree as it is caused by the circumstances in which this organic substance is used in general from 0.01 to 10 percent by weight, preferably 0.05 to 5 percent by weight, used The concentration required in each case in practice can be determined by means of an oxidation test, as described below

the Borazarover

will. Taking into account the general conditions that bond (s) are used in an effective proportion, the concentration is in particular 0.5 to 2 percent by weight, based on the total mixture, i.e. that to be stabilized organic substance with (a) further component (s) optionally contained therein.

The inventive organic substances can also Borazaro compounds (a) and optionally other oxidation

1098A9 / U11

Inhibitors (b) contain other conventional additives, e.g. VI improvers, rust inhibitors, metal deactivators, antifoams, detergents and / or agents for improving the combustion or the octane or cetane number.

The example illustrates the invention.

example

Several borazaro compounds which are suitable according to the invention are produced in the manner described above and prepared using a method. ^J -.- vfcion of 1 percent by weight each with conventional oxidation inhibitors and some corresponding isoelectronic aromatic compounds in terms of suitability as additives for a synthetic lubricating oil of the following composition:

Components Shares,

Weight percent

ρ, ρ'-dioctyldiphenylamine I.

alkylated phenyl-ß-naphthylamine 1

Tritolyl phosphate · 1

5,5'-methylenebisbenzotriazole 0.025

Mono- and dipentaerythritol ester mixture remainder

The aforementioned lubricating oil is commercially available.

mentioned
The offset with the hereinafter / additives lubricating oils are tested by means of a blow Oxydätionstests, wherein the following conditions are applied: the moist air flow rate: 15 liters / hr Test temperature: 216 ⁰ C

Sample volume: 50 ml.

109849/1411

Tabel
Additive InäuVctiona peri ociü _u _h__

none. 25 '

Bis- (9-phenanthryl) -ätker ■ <25 * '

BiS- (IO, 9 ~ borazarophenanthryl) ether 85

10 ~ ethoxy-10,9-borazarophenanthrene 76

10-ethyl-10,9-borazarophenane 60

10-benzyl-10,9-borazarophenanthrene 70

Bis (4,3-borazaro-4 "isoquinolyl) ether 68

Phenylboronic acid. ς 25

Aminoethylphenylborinate 26 '

Diphenanthryl ether 25

3,7-dioctylphenothiazine 52 '

Phenyl-ct-naphthylamine 48).

* ) 9-Hydrox3'-phenanthrene 25

^J Equivalent values.

From the results listed in the table it can be seen that the borazaro compounds suitable according to the invention themselves in the very harsh conditions of this test a we sent better one have an inhibiting effect on the oxidative degradation of the base oil than the known additives. Particularly Noteworthy are the beneficial results obtained with the borazaro compounds in comparison with phenylboronic acid and Aminoäthylphenylborinat can be achieved.

1098A9 / U1 1

Claims (1)

Patentans ρ r u c e 3 .. organic substances containing oxidation inhibitors, in particular fuels or fuels and lubricants, characterized in that they (a) at least one Sorazaro compound and optionally additionally (b) contain at least one conventional antioxidant. 2. Organic substances according to claim 1, characterized in that the borazaro compound (s) have one of the general formulas I to V has (have) .R (D (R " ¹ ). CR '") _X (H) (RUi) "η (III) 109 849/14 (RiM) (R ^{s f} 'X where R is a hydrogen atom or a hydrocarbon radical, the radicals R ', R ". and R" ^{1 are} identical or different and halogen atoms, hydroxyl groups, optionally halogenated oxyhydrocarbyl radicals or optionally halogenated hydrocarbon radicals, preferably aliphatic or cycloaliphatic hydrocarbon radicals, aryl - Or represent aralkyl radicals, where the radicals R and R "'taken together can also form a cyclic structure, χ has the value 0 or is an integer from 1 to 4, y is 0, 1 or 2, ζ is 0 or 1 and the radicals X each represent an atomic group such that two adjacent radicals X taken together form a radical - B. N - R "" R form and the remaining radicals X are carbon, nitrogen, oxygen or sulfur atoms or another remainder - B N - ι ι R "" R
form, where R ^{ini is} a halogen atom, a hydroxyl group, a 10 9 8 4 97 U 1 1 ■ " ¹⁷ " 2 1 2 6 A 5 1 optionally halogenate carbon / hydrogen residues, one optionally halogenated oxyhydrocarbyl radical or a bridging acid toff atom means borazaro compound ejxier to a boron atom, and where in the formulas I to V very generally one or more of the carbon atoms of any aromatic ring by ' (a) nitrogen, oxygen, sulfur or boron atom (s) can be replaced. , 3. Organic substances according to claim 1 or 2, characterized in that that they are BiS- (IO, 9-borazarophenanthryl) -ether contain. 4. Organic substances according to claim 1 to 3> characterized in that that they are 10-Äthox3r-10,9 ~ borazarophenanthren contain. 5. Organic substances according to claim 1 to 4, characterized in that that they contain 10-ethyl-10,9-borazarophenanthrene. 6. Organic substances according to claim 1 to 5 »characterized in that that they contain 10-benzyl-10,9-borazarophenanthrene. 7. Organic substances according to claim 1 to 6, characterized in that that they are bis- (9-ethyl-10,9-borazarophenanthryl) ~ ether included. 8. Organic substances according to claim 1 to 7, characterized in that they contain bis (4,3-borazaro-4-isoquinolyl) ether. 1098A9 / U11 9. Organic substances according to claim 1 to 8, characterized in that that they contain a liquid fuel or fuel as a basic component. 10. Organic substances according to claim 1 to 8, characterized in that that they are used as a basid component Lubricating oil, preferably a synthetic lubricating oil, in particular an ester oil., Especially an oil based on at least one Pentaerythritol esters, rs, included. 11. Organic substances according to claim 1 b: s 10, characterized in that that the concentration of the borazaro compound (s) 0.01 to 10 percent by weight, preferably 0.05 to 5 percent by weight, in particular 0.5 to 2 percent by weight, based on each case on the total substance. 109849/1411