US3069445A

US3069445A - Organo bimetallic compounds

Info

Publication number: US3069445A
Application number: US120151A
Authority: US
Inventors: Richard D Gorsich
Original assignee: Ethyl Corp
Current assignee: Ethyl Corp
Priority date: 1961-06-28
Filing date: 1961-06-28
Publication date: 1962-12-18
Anticipated expiration: 1979-12-18

Description

Unite tates Patent Ofitice 3,%9,445 Patented Dec. 18, 19%2 3,969,445 @RGANU .BEMETALLEC CEEMPUUNDd Richard D. Gorsich, Eaton Rouge, 1121., assignor to Ethyl Corporation, New York, NHL, a corporation of Delafor other purposes.

The compositions of this invention are organo bimetallic compounds of the general formula In this formula R is a cyclopentadienyl or alkylor acylsubstituted cyclopentadienyl group containing from 5 to about 18 carbon atoms, or is an indenyl or fluorenyl group; R is a hydrocarbon group, preferably an alkyl, aryi, cycloalkyl, arailtyl, alkaryl, or alkenyl radical containing from 1 to about 18 carbon atoms; M is an element of group lV-A of the periodic system having an atomic number from 14 to 82, inclusive, i.e., silicon, germanium, tin or lead; M is an element of group IV-B, V-B or Vl-B of the periodic system having an atomic number from 22 to 74, inclusive, i.e., titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum or tungsten; a is 4 when M is a group IVB metal and is 3 when M is a group V-B or VI-B metal; bisl,2or3;cis1,2or3;thesumof2bandcis4 when M is a group V-B metal and the sum of b and c is 4 when M is a group IV-B or Vl-B metal; and d is 2 when M is a group V43 metal and is 1 when M is a group lV-B metal or VI-B metal.

compositions of this invention are, in general, liquid or low-melting solid compounds which are stable at ordinary temperaturesand which can readily be prepared and stored without special precautions for future use. The lead compounds melt, in general, at lower temperatures than the corresponding tin compounds and the melting points tend to increase with the number and molecular weights of the organic substituents designated above as R.

These compounds vary in color from white through yeliow to orange. The depth of color tends to increase with the atomic weight of the group IVA metal and with the number of the group IV-B, VB or VI-B metal carbonyl groups in the molecule.

The compounds of this invention in general are soluble in organic solvents such as aliphatic and aromatic hydro carbons, e.g., n-hexane, petroleum naphtha and benzene, in alcohols such as ethanol and hexanol, in halohydrocarbons such as methylene dichloride and carbon tetrachloride, in others such as diethyl ether, methyl ethyl ether and tetrshydrcftn'an in mixtures of foregoing.

Of the metals represented by M in the above formula, lead is preferred for several reasons. It is readily separated from its ores, is available in large quantities and is considerably cheaper than the other metals. Consequently, the lead compounds of the invention are more adapted for preparation on a larger scale thereby taking advantage of the economies normally associated with large scale operations.

The novel compounds of this invention are of value in the chemical and allied arts. For example, the lead compounds are potent antiknoclc agents and in this utility they are versatile agents in that they are highly efiective group having up to 8 in both unleaded and conventional leaded gasolines made from a wide variety of base stocks. Of the compounds encompassedby this invention, those containing both lead and vanadium are preferred as antidetonants because of the powerful antiknock effects produced thereby. The most outstanding 'antiknocks are the dialltyllead cyclopcntadienyl vanadium tricarbonyls, especially those compounds in which the alkyl groups are methyl or ethyl or a combination of these.

Thus, gasoline fuel compositions containing the novel compounds of this invention in amounts sufficient to increase the antiknock rating thereof and, in particular, those containing a dialkyllead cyclopentadienyl vanadium tricarbonyl, are highly effective fuels for internal combustion engines, the use of which is characterized by smoothness of engine operation.

That the compounds of this invention are highly versatile is shown by the fact that their use as antiknock additives not only involves clear-i.e., unleadedfuels but includes leaded fuels as well, that is, fuels containing a previously known allcyllead antiknock compounds such as tetraethyliead or containing a mixture of such alkyllead compounds. Thus, a liquid hydrocarbon fuel for Otto cycle engines containing antiknock-increasing amounts of both a tetraalkyllead compound and a lead-containing compound of this invention is superior in antiknock effectiveness to the same fuel containing a like amount of either of said compounds in the absence of the other. Best results occur when the concentration of the tetraalizyllead compound is equivalent to from about 0.5 to 6.0 grams of lead per gallon and the concentration of the carbonyl compound is equivalent to from about 0.01 to 4.0 grams of lead per gallon.

The preferred antiknock fuels of the invention (because of their economy and availability) are leaded or unleaded gasolines containing a compound of the formula wherein M is tin or lead; R is a cyclopentadienyl or lower alkylor acyl-substituted cyclopentadienyl group, e.g., methyl cyclopentadienyl or acetyl cyclopentadienyl, or is an indenyl or fiuorenyl group, and R is a lower alkyl group, e.g., methyl, ethyl, pentyl, etc., or is an aryl carbon atoms, e.g., phenyl, tolyl, Xylyl, etc.

addition to their effectiveness as antiknock agents for hydrocarbon fuels, the compounds of this invention are excellent lubricant additives. In this application, as well as in fuels, they exhibit unusual versatility. Thus, when dissolved in lubricants, they effectively improve the ricating properties thereof, greatly reduce engine wear, virtually eliminate frictional damage, and/ or bring about overients in stability. Their versatility is further a .ested to by the wide variety of natural and synthetic lubricant bases in which they produce the above effects. For example, they are highly effective for the above and other purposes in such lubricating and industrial oils as crankcase lubricating oils, transformer oils, turbine oils,

transmission fluids, cutting oils, glass annealing oils, gear oils, mineral white oils, oils thickened with soaps and inorganic thickening agents, hydraulic fluids and, in general, engine and industrial oils which are derived from crude petroleum or produced synthetically.

Typical of these synthetic lubricants are the polybutene oils, the ester oils, the silicone oils, phosphates, phosphonates and the like. The ester oils include such compounds as di-Z-ethylhexyl sebacate, di-sec-amyl-sebacate, di-Z-ethylhexyl azelate, di-3-methylbutyl adipate, di- Z-ethylhexyl adipate, diisooctyl adipate, di-Z-ethylhexyl phthalate, dibutoxyethyl phthalate, pentaerythritol tetracaproate, triethylene glycol .di-Z-ethylhexanoate and d polyethylene glycol di-Z-ethylhexanoate. Examples of the silicone oils are the dimethyl, divinyl, diphenyl, methyl vinyl, methyl pheuyl, diethyl, dibutyl, di-pbromophenyl, di-p-chlorophenyl, di-p-fiuorophenyl, di-m-trifluoromethylphenyl, di-p-phenoxyphenyl, di-m-chlorophenyl, di-3,4-dichlorophenyl, di-3-chloro-4-bromophenyl, di-pmethoxyphenyl and di-p-cyanophenyl siloxanes, i.e., silicone derivatives.

Among the most effective compounds of this invention as lubricant additives are those containing vanadium bonded to lead and particularly to tin. Thus, these are the preferred lubricant additives for use in accordance with this invention.

Accordingly, hydrocarbon lubricant compositions containing, in amounts sufficient to improve the lubricating properties thereof, the novel compounds of this invention wherein M is vanadium and M is lead or tin and, in particular, those containing a dialkyltin cyclopentadienyl vanadium tricarbonyl, are effective lubricants for internal combustion engines and for other applications.

An excellent feature of these lubricant additives is that they can be used not only in a wide variety of oils but also in combination with other additives without in any Way impairing their eifectiveness or that of the other additives. Such other additives include, for example, antioxidants, metal deactivators, detergents-dispersants, pourpoint depressants, viscosity index improvers, antifoam agents, corrosion inhibitors, oiliness or film strength agents, dyes and the like.

The preferred lubricants of the invention are the cheap and readily available liquid hydrocarbon crankcase lubricating oils containing from about 0.05 to about 5.0 weight percent of vanadium as a compound of the formula wherein M is tin or lead, R is a cyclopentadienyl or lower alkyl or acyl cyclopentadienyl group, e.g., methylcyclopentadienyl or acetylcyclopentadienyl, or is an indenyl or fluorenyl group, and R is a lower alkyl group, e.g., methyl, ethyl, pentyl, etc., or is an aryl group having up to about 8 carbon atoms, e.g., phenyl, tolyl, xylyl, etc.

In addition to the foregoing uses, the compounds of this invention find application as plasticizers and stabi lizers for vinyl and other synthetic resins such as polyvinyl chloride.

The compounds of this invention are best prepared by reacting an alkali metal derivative of a cyclopentadienyl or alkyl or acyl cyclopentadienyl carbonyl of a metal of group IV-B, VB or VLB of the periodic system (titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum or tungsten) with an organo metal halide of a metal of group IV-A of the periodic system (silicon, germanium, tin or lead). In this reaction, the alkali metal of the carbonyl reactant is replaced by the organometallic radical of the halide reactant. The carbonyl reactants used in this process are preferably alkali metal cyclopentadienyl or alkali metal alkyl or acyl cyclopentadienyl carbonyl compounds of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum or tungsten having the formula RM co ,M

wherein R is a cyclopentadienyl or alkyl or acyl cyclopentadienyl group, or is an indenyl or fluorenyl group, M is titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum or tungsten, i.e., a group IV-B, VB, or VI-B element having an atomic number of 22 through 74, inclusive (Periodic Chart of the Elements, Fischer Scientific Company, New York, 1957), M is lithium, sodium, potassium, rubidium or cesium, i.e., a group I-A element having an atomic number of 3 through 55, inclusive, a is 4 when M is a group lV-B metal and is 3 when M is a group V-B or VI-B metal, and e is 2 when M is a group VB metal and is 1 when M is a group IV-B or VI-B metal. Of the group 4; LA metals, sodium and potassium are preferred because of their availability, reactivity, and economy and, of the group IVB, V-B and VI-B metals (i.e., M), vanadium is preferred for the reasons noted above.

The halide reactants are mono-, dior triorganometal halide compounds having the formula wherein M is silicon, germanium, tin or lead, i.e., an element of group IV-A of the periodic system having an atomic number from 14 to 82, inclusive; X is halogen; f is 1, 2 or 3; and R is an alkyl, aryl, cycloalkyl, aralkyl, alkaryl or alkenyl radical; and wherein the several R groups can be the same or different. Generally speaking, each of the R radicals contains up to about 18 carbon atoms. Of the halogens, chlorine is preferred because the organic chlorides of M are generally more stable and more soluble in organic solvents than the bromides and iodides and are more reactive than the fluorides. Further, chlorine is the cheapest of the halogens and therefore, the organic M chlorides are more economical to prepare than any of the other halides. In this process M is preferably tin or lead since the reaction proceeds very smoothly for these metals giving good yields of especially valuable products.

In general, the halide groups of the halogen reactants are completely replaced by the cyclopentadienyl metal carbonyl groups of the carbonyl reactant, one cyclopentadienyl metal carbonyl group being present in the formula of the product for each halogen atom originally present in the halogen reactant. The reaction product may on occasion he a mixture of mono-, diand trisubstitution products which can readily be separated by solvent extraction, fractionation or other appropriate means.

The reaction of this invention is normally carried out in an inert organic solvent. Ethers are generally preferrecl because of their solvent power for the reactants, and tetrahydrofuran is particularly preferred because of the ready solubility of the reactants therein, its volatility and consequent ease of separation from the reaction products and the ease with which the solvent may be made and kept anhydrous.

The reaction of this invention proceeds smoothly and rapidly at moderately elevated temperatures, reaching completion for the reaction of lower alkyl derivatives of the group IV-A metal halides with carbonyl reactants containing an unsubstituted cyclopentadienyl radical-in 15 minutes to a half hour at 50100 C. Somewhat longer reaction times are desirable for the higher alkyl and the substituted cyclopentadienyl derivatives. The reaction temperature can vary from room temperature or below to the normal reflux temperature of the solvent or even higher if pressure is employed. However, elevated temperatures should be used with care since prolonged heating at reflux may cause some decomposition of the reaction product. The pressure employed may range from 10 millimeters of mercury or less to atmospheres or more, but in general, normal atmospheric pressure is wholly satisfactory and preferred.

The invention will be more fully understood by reference to the following set of illustrative examples in which all parts and percentages are by Weight.

Example I A solution of 7.9 parts (0.03 mole) of molybdenum carbonyl, Mo(CO) and 3.2 parts (0.036 mole) of cyclopentadienylsodium in 200 parts of tetrahydrofuran was refluxed overnight. To the resulting yellow mixture, containing the so-formed cyclopentadienyl molybdenum tricarbonyl sodium, was added 3.6 parts (0.015 mole) of dimethyltin dichloride. The mixture was briefly heated to reflux and then the solvent was evaporated in vacuo. The residue was extracted with methylene dichloride. The methylene dichloride extract was evaporated and the residue was recrystallized from a mixture of methylene dichloride and n-hexane to give 2.6 parts (27 percent) of large yellow crystals of dimethyltin bis(cyclopentadienylmolybdenum tricarbonyl) [CpivEo(CG) Snl\/i e melting with decomposition at 155-160 C.

Analysis.Calculated C 33.84, H. 2.53. 33.85, H 2.52.

Found C Example 11 When 6.95 parts of potassium methylcyclopentadienyltitanium tetracarbonyl are reacted with 9.36 parts of triethyllead bromide in 730 parts of benzene at 50 C. for a period of 15 minutes, methylcyclopentadienyltitaniurn tetracarbonyl triethyllead is obtained.

Example 111 Methylethylcyclopentadienylzirconium tetracarbonyl rubidium and dibutylsilicon diiodide in the proportion of 9.9 parts of the former to 4.9 parts of the latter are dissolved in 670 parts of toluene and are reacted at 80 C. for a period of 15 minutes. The product, bis(methylethylcyclopentadienylzirconium tetracarbonyl) dibutylsilicon may be purified by recrystallization from anhydrous ethanol.

Example I V Dimethylcyclopentadienylhafniurn tetracarbonyl cesium (13.2 parts) and n-octylgermanium trichloride (2.43 parts) are dissolved in 700 parts of o-xylene. The mixture is stirred for 15 minutes at 85 C. The product is tris(dimethylcyclopentadienylhafnium tetracarbonyl) noctylgermanium.

Example V A mixture of 6.75 parts of diethylcyclopentadienyl- Vanadium tricarbonyl dilitnium and 15.4 parts of di-ndodecyltin dibrornide is dissolved in 1000 parts of mixed hexancs and heated to reflux for a half hour. The prodnot is the dimer of diethylcyclopentadienylvanadium tricarbonyl di-n-d'odecyltin.

Example VI To 8.60 parts of butylcyclopentadienylniobiurn tricarbonyl disodium, 22.8 parts of dicetyllead diiodide is added and the mixture is dissolved in 1410 parts of nhexene. The solution is heated to reflux for a period of 1 hour. The dimer of butyicyclo-pentadienylniobium tricarbonyl dicctyllead is obtained.

Example VH When 13 parts or" octadecylcyclopentadienylmolybdenum tricarbonyl sodium and 5 .2 parts of acetylcyclohexyl- -tin triiodide are mixed with 820 parts of petroleum naphtha and the mixture is heated under reflux for a period of 1 /2 hours. tris(octsdecylcyclopentadienylmolybdenum tricarbonyl) acetylcyclohexyltin is obtained.

Example X To 16 parts of octadecylmethylcyclopentadieny1tung-- sten tricarbonyl potassium, 12 parts of triphenyllead chlo-- ride is added and the mixture is dissolved in 1250 parts of ether. The resulting mixture is heated to reflux for hour. The product is octadecylrnethylcyclopentadienyltungsten tricarbonyl triphenyllead.

Example XI 10 parts of didodecylcyclopentadienyltitaniurn tetracarbonyl lithium is added to 4.6 parts of dibenzylsilicon dibrornide and the mixture is treated with 660 parts of the diethyl ether of diethyiene glycol. Reaction for 1 hour at 80 C. results in the formation of bis(didodecy1- cyclopentadienyltitanium tetracarbonyl) dihenzyl silicon.

Example XII 9.0 parts of methylbutylcyclopentadienylzirconium tetracarbonyl sodium is reacted With a mixture of 4.6 parts of phenethylgerrnanium triiodide and 620 parts of the dihutylether of diethylene glycol. The mixture is heated to C. and maintained at that temperature for 1 hour. Tris(methylbutylcyclopentadienylzirconium tetracarbonyi) phenethylgermanium is obtained.

Example XIII Tetrahydrofuran solutions of 11.1 parts of indenylhafnium tetracarbonyl potassium and 10.7 parts of tri-otolyltin chloride are mixed and the mixture is dissolved in 980 parts of tetrahydrofuran. The product is indenyl hafnium tetracarbonyl tri-o-tolyltin.

Example XI V A mixture of 7.9 parts of fiuorenylvanadium tricarbonyl dilithium, 14.4 parts of dixylyllead dibromide and 101 parts of benzene is heated to C. for a period of 1 /2 hours. The dimer of iiuorenylvanadium tricarbonyl dixylyllead is obtained.

Example XV A mixture of 8.3 parts of acetylcyclopentadienylniobium tricarbonyl disodium, 10.3 parts of dicyclopentadienylsilicon diiodide and 840 parts of toluene is heated to 60 C. for a period of /2 hour. The product is the dimer of acetylcyclopentadienylniobium tricarbonyl dicyclopentadienylsilicon.

Example XVI 16.5 parts of octadecylcyclopentadienyltantalum tricaroonyl dipotassium is added to a mixture of bis(niethylcyclopentadienyl)germanium difluoride (6.7 parts) With 1080 parts of o-xyiene and the mixture is stirred at C. for 1 hour. The product is the dimer of octadecylcyclopentadienyltantalum tricarbonyl bis(methylcyclopentadienyl) germanium.

Example XVII 5.2 parts of cyciopentadienylchromium tricsrbonyl lithium is dissolved in 540 parts of mixed hexanes and the solution is mixed with 6.9 parts or" bis(ethylpropylcyclopentadienyl)tin dibrornide. The mixture is heated to reflux for a half hour. The product is bis(cyclopentadienylchroniium tricarhonyl) bis(ethylpropylcyclopentadienyl tin.

Example XVIII When 7.1 parts of rnethylcyclopentadienylmolybdenum tricarbonyl sodium is reacted with 5.0 parts of methyllead triiodide in 540 parts of n-hexane under reflux [or a period of 15 minutes tris(methylcyclopentadienylmolybdenum tricarbonyl) methyllead is obtained.

Example XIX Ethylcyclopentadienyltungsten tricarbonyl potassium and triethylsilicon chloride in the proportion of 10 parts of the former to 3.8 parts of the latter are dissolved in 520 parts of methylene dichloride and are reacted at 60 C. for a period of 15 minutes. The product is ethylcyclopentadienyltungsten tricarbonyl triethylsilicon.

Example XX Methylethylcyclopentadienyltitanium tetracarbonyl lith- 7 ium (6.9 parts) and dibutylgermanium difiuoride (2.81 parts) are dissolved in 500 parts of n-octane. The mixture is stirred for a half hour at 60 C. The product is bis(methylethylcyclopentadienyltitanium tetracarbonyl) dibutylgermanium.

Example XXI 8.0 parts of dimethylcyclopentadienylzirconium tetracarbonyl sodium and 5.1 parts of n-octyltin triiodide dissolved in 590 parts of petroleum naphtha are heated under reflux for 1 hour. The product is tris(dirnethylcyclo pentadienylzirconium tetracarbonyl) octyltin.

Example XXII A mixture of 11.3 parts of diethylcyclopentadienylhafnium tetracarbonyl potassium and 15.6 parts of tri-anaphthyllead chloride is dissolved in 1210 parts of diethyl ether and heated under reflux for one and onequarter hours. The product is diethylcyclopentadienylhafnium tetracarbonyl tri-a-naphthyllead.

Example XXIII To 6.8 parts of butylcyclopentadienylvanadium tricarbonyl dilithium, 6.8 parts of diallylsilicon dibromide are added and the mixture is dissolved in 610 parts of the diethyl ether of diethylene glycol. The solution is stirred for a half hour at 60 C. The dimer of butylcyclopentadienylvanadium tricarbonyl diallylsilicon is obtained in good yield.

Example XXIV Octylcyclopentadienylniobium tricarbonyl disodium, divinylgermanium fluoride and the dibutyl ether of diethylene glycol are combined in the ratio 102412880. The mixture is reacted at a temperature of 60 C. for a period of a half hour. The product is the dimer of octylcyclopentadienylniobium tricarbonyl divinylgermanium.

Example XXV When 15.8 parts of cetylcyclopentadienyltantalum tricarbonyl dipotassium and 10.7 parts of dimesityltin dichloride are mixed with 1190 parts of tetrahydrofuran and the mixture is heated under reflux for 1 hour, the dimer of cetylcyclopentadienyltantalum tricarbonyl dimesityltin is obtained in good yield.

As stated above, the compounds of this invention are extremely useful as antiknock agents for internal combustion engine fuels. The following specific examples serve to illustrate the antiknock use of the said compounds.

Example XXVI A base stock is prepared by mixing 24 volumes of isopentane, 66 volumes of isooctane and 10 volumes of cumene. To this base stock is added 0.75 gram of lead per gallon as a mixture (296.0 parts) containing 5.5 percent of tetramethyllead, 24 percent of trimethyL ethyllead, 37.5 percent of dimethyldiethyllead, 26 percent of methyltriethyllead and 7 percent of tetraethyllead. To the resulting mixture are added 79.1 parts (0.70 theory) of 1,2-dichloropropane and 145.6 parts (0.775 theory) of ethylene dibromide. Finally, 0.15 gram of molybdenum per gallon as bis(cyclopentadienylmolybdenum tricarbonyl) dimethyltin is added. A significant increase in knock rating accompanies the final addition.

Example XX VII When the base stock of Example XXVI is treated with 1.2 grams of vanadium per gallon as the dimer of di ethylcyclopentadienylvanadium tricarbonyl didodecyltin, an increase in knock rating is observed.

Example XX VIII Atetraethyllead fluid is prepared by mixing 323.5 parts of tetraethyllead with 144.8 parts (0.60 theory) of nhexyl chloride and 156.2 parts (0.625 theory) of mixed dibromotoluenes. The resulting fluid is mixed with a suflicient amount of a base fuel consisting of 15 percent by volume of alkyiate gasoline and 85 percent of catalytically cracked gasoline to give a lead concentration of 1.25 grams of lead per gallon. The addition to this blended fuel of 0.16 gram of titanium per gallon as ethylcyclopentadienyltitanium tetracarbonyl trimethyltin increases the antiknock value thereof.

The following examples serve to illustrate the antiwear utility of the compounds of this invention. All percentages given in these examples are by weight.

Example XXIX To the Mid-Continent oil of Example XXIX is added 1.5 percent of bis(cyclopentadienyltitanium tetracarbonyl) dibenzyltin. This addition results in a marked diminution in wear as tested by the 4-ball Wear machine.

As indicated above, a wide variety of organo bimetallic compounds fall within the scope of this invention. Examples of these compounds are the following: cyclopentadienyltitaniurn tetracarbonyl trimethylsilicon, bis(methylcyclopentadienyltungsten tricarbonyl) dibenzylgermanium, dimer of butylisooctylcyclopentadienylnobium tricarbonyl bis-2,4-xylyltin, tris(diethylcyclopentadienylzirconium tetracarbonyl) cyclohexyllead, dimer of fluorenylvanadium tricarbonyl dimesitylsilicon, indenylchromium tricarbonyl triisobutylgermanium, bis(methylpropylcyclopentadienylhafnium tetracarbonyl) dicetyltin, dimer of cyclopentadienyltantalum tricarbonyl ditolyllead, tris(vinylcyclopentadienylrnolybdenum tricarbonyl) vinylsilicon, isobutylcyclopentadienyltitanium tetracarbonyl tri-n-octylgermanium, bis(isopropylcyclopentadienylchromium tricarbonyl) dicyclopentyllead, bis(butylisooctylcyclopentadienylzirconium tetracaroonyl) diethylsilicon, dimer of hexylcyclopentadienylniobium tricarbonyl diphenylgermanium, cyclopentadienylhafnium tetracarbonyl triphenyl ead, dimer of methylethylcyclopentadienyltantalum tricarbonyl divinylsilicon, and tris(fluorenyltungsten tricarbonyl) cyclohexylgermanium. Of the foregoing compounds, those wherein the group IV-A metal is lead or tin, the group V-B metal is vanadium and the organoradical is cyclopentadienyl or indenyl or a substitution product thereof are preferred because of their ease of preparation and because of their high effectiveness as antiknock and antiwear agents. Particularly preferred compounds, for the reasons given above, include the dimer of indenylvanadium tricarbonyl diallyltin, methylisooctylcyclopentadienylmolybdenum tricarbonyl trioctadecyltin and bis(methylcyclopentadienyltitanium tetracarbonyl) diphenyllead.

In making the valuable compounds of this invention, a wide variety of reactants are available. The alkali metal simple or substituted cyclopentadienyltitanium (or other group IVB, V-B or VIB metal) carbonyl is made by the reaction of the appropriate inorganic metal carbonyl with the cyclopentadienyl alkali metal compound in tetrahydrofuran or other suitable solvent. The mixture is heated to reflux until the reaction is essentially complete. The reaction mixture is then used without further treatment for the reaction of the invention. Illustrative of these compounds are cyclopentadienylrnolybdenum tricarbonyl lithium, dibutylcyclopentadienyltantalum tricarbonyl disodium, fluorenyltitanium tetracarbonyl potassium, methylethylcyclopentadienylchromium tricarbonyl rubidium and octylcyclopentadienylzirconiurn tetracarbonyl cesium.

Methods for the preparation of organometal halides the other reactants in the process of this inveution are described by E. Krause and A. von Grosse ill Dlfi Chemie der MetalLOrganischen Verbindungen, Borntraeger, Berlin, 1937. Examples of such compounds include triphenyltin chloride, dimethyltin dichloride, triphenyllead chloride, diethyllead dichloride, dimethylsilicon difluoride, tris(ethylcyclopentadienyl)silicon iodide, bis(dodecylcyclopentadienyl) germanium dibromide, bis(ethylphenyl)tin dichloride, and bis(acetylcyclohexyl)lead dibromide.

The reactants-RM(CO),M and R l\/l X -used in the preparation of the compounds of this invention can be employed in proportions ranging from a 100 percent or greater excess of the group IVB, VB, or V'IB compound to a 100 percent or greater excess of the group lV-A halide compound. Usually, they are employed in proportions corresponding approximately to stoichiometric equivalents but a moderate excess of onereactant or the other is oftenused to bring about an increased reaction rate.

Amon the criteria for the choice of solvents to be employed in the reactions of this invention are that the solvents be liquid under the reaction conditions and that they be inert to both reactants and products. Accordingly, the solvents may include, in general, aromatic hydrocarbons such as benzene, toluene, the Xylenes and the like, aliphatic hydrocarbons such as hexanes, heptanes, octanes, petroleum naphtha and the like, aliphatic or aromatic others such as dietbyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether or tetrahydrofuran, aliphatic alcohols such as methanol, ethanol, isopropanol, the pentanols, etc., and halohydrocarbons such as methylene chloride and carbon tetrachloride, and the like. The preferred solvent is tetrahydrofuran because of its relatively high solubility for the reactants and for the other reasons mentioned above.

The reaction of this invention may be carried out at any temperature Within the normal liquid range of the solvent or at higher temperatures if tLB liquid phase is maintained by the application of pressure. The normal reflux temperature is perfectly satisfactory in most instances but care should be taken not to employ too high a temperature for too long a time inasmuch as excessive temperatures may cause more or less extensive decomposition of the products. Thus, temperatures in the range of to 200 C. are employable, although best results are obtained between 50 and 100 C., and this range is therefore preferred.

Because the reaction usually proceeds rapidly under reflux at normal pressure, atmospheric pressure is usually satisfactory but pressures ranging from millimeters of mercury to 100 atmospheres may be used if desired.

The reaction of this invention may be carried out under any atmosphere inert to both reactants and products. The lead and tin compounds are stable on exposure to dry air which can thus be used with safety. The use of dry nitrogen is preferred for the less stable germanium and silicon compounds. Other suitable protective atmospheres include gaseous saturated hydrocarbons such as methane and ethane and the noble gases, helium, neon, argon, krypton and xenon.

The normally solid compounds of this invention are soluble in and can be purified by recrystallization from a variety of organic solvents. Specifically, simple aromatic solvents such as benzene or toluene, simple aliphatic solvents such as hexane, alcohols such as ethanol and halohydrocarbons such as methylene chloride, and their mixtures, are found to be satisfactory.

In the improved fuels of this invention, organic halide scavengers can be employed. These scavengers can be either aliphatic or aromatic halohydrocarbons or a combination of the two having halogen attached to carbon in either the aliphatic or aromatic portion of the molecule. These scavengers may also be carbon-, hydrogenand oxygen-containing compounds such as haloallryl ethers, halohydrins, halonitro compounds and the like. Still other examples of scavengers that may be used in this invention are illustrated in U.S. Patents 1,592,954; 1,668,022; 2,398,281; 2,479,900; 2,479,901; 2,479,902; 2,479,903; 2,496,983; 2,661,379; 2,822,252; 2,849,302; 2,849,303 and 2,849,304. Mixtures of different scavengers may also be used. Concentrations of organic halide scavengers ranging from about 0.2 to about 2.5 theories based on the lead are usually sufficient although greater or lesser amounts may be used. Thus, in general, use is made of an amount of organic halide scavenger that is capable of reacting with the lead during engine combustion to form relatively volatile lead halide and thereby effectively control the amount of deposit formed in the engine.

The fuels of this invention can contain other additives. Typical of these are antioxidants (e.g., N,N'-di-sec-butylp-phenylenediamine; p-N-butylaminophenol; 4-methyl-2, 6-di-tert-butyl-phenol; etc.), metal deactivators (e.g., N,N'-disalicilideue-1,2-diaminopropane, etc.), dyes, phosphorus additives (e.g., tri(/3chloropropyl)thionophosphate, dimethyltolylphosphate, dimethyl-xylylphosphate, phenyldimethylphosphate, tricresylphosphate, phenyldicresylphosphate, cresyldiphenylphosphate, trimethylphosphate, etc.), boron additives, corrosion inhibitors, detergents, antiicing additives, other antiknock agents (e.g., methylcyclopentadienylmanganese tricarbonyl, cyclopentadienylmanganese tricarbonyl, cyclopentadienylnickel nitrosyl, manganese pentacarbonyl, iron carbonyl, dicyclopentadienyliron, etc.), induction system cleanliness additives, top cylinder lubricants and the like.

Having thus described the process and novel products 05 this invention it is not intended that it be limited except as set forth in the following claims.

I claim:

1. A compound represented by the general formula wherein R is a radical selected from the group consisting of cyclopentadienyl, alkylcyclopentadienyl and acylcyclopentadienyl radicals containing from 5 to about 18 carbon atoms, and of indenyl and fiuorenyl radicals; R is a radical selected from the group consisting of allryl, aryl, cycloalkyl, aralkyl, alkaryl and alkenyl radicals containing from 1 to about 18 carbon atoms; M is an element selected from the group consisting of the elements of group IVB of the periodic system having atomic numbers from 22 to 72, inclusive, the elements of group V-B of the periodic system having atomic numbers from 23 to 73, inclusive, and the elements of group VI-B of the periodic system having atomic numbers from 24 to 74, inclusive; M is an element of group IV-A of the periodic system having an atomic number from 14 to 82, inclusive; :2 is 3 when M is an element selected from the group consisting of the elements of groups V-B and VLB of the periodic system and is 4 when M is an element of group lV-B of the periodic system; b is an integer from 1 to 3, inclusive, c is an integer from 1 to 3, inclusive; the sum of b and c is 4 when M is an element selected from the group consisting of the elements of groups IV-B and VI-B of the periodic system; the sum of 2b and c is 4 when M is an element of group V-B of the periodic system; and a. is 2 when M is an element of A 1. 1. which comprises reacting a compound represented by the general formula RM co ,,M

wherein a is 3 when M is an element selected from the group consisting of the elements of groups V-B and VI-B of the periodic system and is 4 when M is an element of group IV-B of the periodic system, M is a metal of group I-A of the periodic system, e is 1 when M is an element selected from the group consisting of the elements of groups IV-B and VIB of the periodic system, and is 2 when M is an element of group V-B of the periodic system, and R is a radical selected from the group consisting of cyclopentadienyl, alkycyclopentadienyl and acylcyclopentadienyl radicals containing from 5 to about 18 carbon atoms, and of idenyl and fiuorenyl radicals, with a compound represented by the general formula wherein X is a halogen, R is a radical selected from the group consisting of alkyl, aryl, cycloalkyl, aralkyl, alkaryl and alkenyl radicals containing from 1 to about 18 carbon atoms, and f is an integer from 1 to 3, inclusive.

, wherein M is sodium and 6. The method of claim X is chlorine.

7. The method of claim 5, wherein M is tin. 8. The method of claim 5, wherein M is tin and M 5 is molybdenum.

9. The method of claim 5, wherein the reaction is carried out in an essentially inert organic solvent.

10. The method of claim 5, wherein the reaction is carried out in an ether as solvent. 10 1]. The method of claim 5, wherein the reaction is carried out in tetrahydrofuran as solvent.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES King et al.: Chem. and Industry, pp. 747-748 (June

Claims

1. A COMPOUND REPRESENTED BY THE GENERAL FORMULA