Procedure for the electro-chemical production of CO-free metal-organic complexes of transition metals

Metaliorgani connections are by definition such connections, in which the metal either over a 6oder a r-Bindnng to an C-atom or a CC - Mehrfachbindun g is bound (S. e.g. J.J.Eisch, The Chemistry OF Organometallic Componnds, The Macmillan Comp., New York, P. 1). Metal-organic complex connections of the transition metals possess large technical interest, there it in many cases active catalysts to the Hydriemng from insatiated organic compounds, to the Oligomerisation of! , A-Diolefinen, to the Mischdimerisation of Olefinen and/or alpine one with 1, 3-Diolefinen (VG!. G. Wilke and Mitarbeiter, Liebip Ann. Chem. Bd. 727, P. 143 to 207) or for example to the Isomerisiemng of Olefinen or to the Oligomerisation of Llkinen is. In a preferential procedure such transition metal complexes become after the German patent “t0 writing No.! 191875 by editorship manufactured by transition metal connections by metal alkyl, - cycloalkyl, - more aryIoder - aralkyl Verbindnngen of metals of the Ith organic compounds complex-forming to lII.Gruppe with present. When complexing agents are possible electron donors, who contain CC multiple being DNN gene or Atomgmppiemngen with not-binding pairs of electrons, like e.g. Alkylund aryl connections of the elements of the V.Hanptgruppe of the periodic system. The organic compounds of the metals of the groups of I, [...] and [...] used as reducing agents are all extremely luftund water sensitive, them catch fire frequently with admission of air or oxygen or react like an explosion with water or alcohols. To its handling it requires from there special precautionary measures (see e.g. Houben Weyl, Präparative methods of organic chemistry, Bd.XIII/4, organic compounds of aluminum, 8,19). In the procedure according to invention metal-organic co-ordination connections of the transition metals will receive in very simple way by an electro-chemical reaction with presence of suitable complexing agents. Metal-organic connections I. up to IIITH group are not needed as reducing agents from there. With the procedure according to invention in a E1ektrolysenzelle between two Metall-Elektroden a Elektrolytlösnng is elektrolysiert, those from a höherwerttgen Übergangsmetollverbindnng, a suitable organic solvent, gegebenenfa! LS Alkalibzw. Tetraalkyl ammonium halide or a similar Leitsalz, nnd a suitable complexing agent exists. It is extraordinary surprising that under these conditions with the electro-chemical reduction that does not take place transition metal being DNN gene a metal separation at the cathode. This metal separation enters immediately, if one the same electrolytes out for example Nickelacetylacetonat, Tetrabutylammoniumbromid and tetrahydrofurane as solvent absence of a complexing agent electrometer. In addition it is well-known that according to invention used the transition metals in elementary form, approximately in form of the metallic powders, when metal semolina or - reacts to granulates, not with effindungsgemäß the used complexing agents. One can assume from there that the transition metal connection at the cathode up to the zerovalent 3fi stage is reduced and, before the metal (O) however with other atoms to a crystal lattice and thus to higher aggregates meets, with in electrolytes present complexing agent for the organ COMET all complex reacted. The electro-chemical reduction of co-ordination connections of the transition metals into complexes of lower Wertigkeitsstnfen is well-known from the Fachliteratnr. Thus for example the elektrochemtsche reduction of at 2, 2 succeeds ' - Bipyridyl komplexierten transition metal cations over several Wertigkeitsstufen up to the oxidation number of O, S. z, B.S. Herzog and R. Taube, Z.Chem. Bd.2, S.208. In the literature is the Abduktion of [(pH) 3 Pj3 - RhC1 to Tetrakistriphenylphosphinrhodium (O) described (D.C. Olson u, W. germ, tnorg, chem. Bd. 8, P. 2028). Also electricalbefore-mix reduction of Dibenzolchrom (I) halide to Dibenzolchrom (O) is admits (C. Fnrlani and E.O. Fischer, Z. electrochemistry Bd. 61, S.481). Übereinstimmendwarin everything so far from the LiteraturbekarmtenFällen the transition metal in its higher Wertigkeitsstnfe before the reduction already with the same complexing agent coordinates, to which it was bound also in the reduced form. In a general chemical reaction lets itself express in such a way: and n+ +peC) +qL _ > [MLm÷@ (NP) + M = Übergangsmeta11 L = complex-forming ligand m = a whole number of n = priority condition of the transition metal PE - = number of the electrons q = change of the co-ordination number. For metal-organic complexes that means that the metal-organic connection must already be present by a higher into a low priority is then reduced. It is well-known from the F oh literature a far electrolytic procedure for the production of nbergangsmetallorganischen connections with Cyclopentadienylresten or substituted Cyclopentadienylresten. With this procedure for example after that USA patent specification No. 2.960.450 or according to a publication of S. Valcher nnd E. Alunni, Päc. Sci. Bd.38, No. 6.527 concerns it one elektrochemiseh accomplished Ummetalliemng one already at metal bound Cyclopentadienylrestes on another metal, for example by electrolysis of a solution of Natriumoder Thallinmcyclopentadienyl on use of an anode out of iron, nickel or manganese according to the following reaction equation: ! 0 2 m Cp + Fe (NJ, Mn) m = well, left, K, T1: - FeCpz .eG .mC) and/or NiCp2 or MnCp2 for the Herste! lung of iron, Nickelbzw. That the Cyclopentadienylrest is already present in a form bound to an auxiliary metal, means Mangancyclopentadienyl connections for example as alkali! 5 eyelopentadienyl and by the electrolysis a Ummetalliemng of the remainder, to it changes also nothing is only forced, if, according to a procedure variant from the USA patent specification No. 2.960.450 the Alkalimetallcyclopentadienyl Verbindnng in the electrolysis cell is again and again formed by reaction of the cathodically separated Alkalimetalis with Cyclopentadien. In dern erfindnngsgemäßen procedures transition metal connections of higher Wertigkeitsstufe in presence of connections are reduced, which opposite that metal in these Werttgkeitsstufe not when complexing agents function. Nevertheless the cathodic separation of Meta11 is omitted, and one receives the complex connections with the metal in the lower or zeroth Wertigkeitsstufe in good yields from approximately 80 to 95%. That means that by the reaction according to invention the metal-organic connection is only formed. With suitable Komplexbildnem the reaction according to invention lets itself use also for the production of zerovalent or least-significant co-ordination connections of the transition metals with alkyl, aryl, Alkyloxyoder Aryloxyverbindungen of the trivalent phosphorus, arsenic or antimony. These are electron donors, who possess a not-binding pair of electrons. An example of it is the production of Tetrakis nickel (O) Ni [(CöHs P] 4 from a bivalent nickel connection, which is not komplexiert at Triphenylphosphin. One keeps nickel (O) Ni [(CöHsO P] 4. similar to Tetrakis. As transition metal connections connections of the transition metals IV. to VIITH Nebengruppe and the VIIITH group of the periodic system, e.g. titanium, zircon, Hafninm, vanadium become. , Prefer chrome, molybdenum, manganese, iron, cobalt, nickel, Palladinm and platinum the metals IV., VI. and VIII, group-assigned, in particular titanium, zircon, hafnium, chrome, iron, cobalt and nickel. The electrolysis become appropriately soleheVerbindungen the Übergangsmeta! le assigned, which are soluble into used Lösungsmittein, such connections are the Metallacetylacetonate, salts of organic acids or salts with other organic remainders, e.g. alkanolate remainders or complex alkanolate remainders like [Al (OC2H6) 4] C). Often also the water-free halides of the transition metals themselves know or in the form of complexes with Lewis bases, for example TiC14, TiC1s. 3 THF, FeG18 or CrC1s. 3 THF to be used (THF = tetrahydrofurane). When complexing agents are possible for the co-ordination connections which can be manufactured according to invention electron donors, who contain CC multiple connections or atomic groupings with nlchtblndenden pairs of electrons. Are particularly suitable: 1. cyclische Mehrfacholefine like e.g. Cyclooctadien (! , g), Cyclooctatetraen, Cyclododecatrien (1, 5, 9); cyclische Monoolefine with strained double bonds or l, 3-Diolefine or alkines; 2. in the class of the Elekttonendonatoren with not-binding pairs of electrons Alkylund aryl connections of elements of the Vth main group of the periodic system, with exception of nitrogen, z, B. tertiary Phesphine, Arsine, Stibine as well as Phosphite. Suitable solvents are aromatic hydrocarbons like e.g. benzene and toluol, aliphatic or cyclo-aliphatic more einoder multi-valued ethers, like e.g. diethylether, Tetrahydmfuran, Dimethoxyäthan or 2, 2 ' - Dimethoxydiäthyläther or other dialkyl ethers of ethylen glycol or the Dioder of tri ethylen glycol; for the procedure according to invention propylene carbonate CH O CH O I CH3 and particularly Pyridin continued to work. Since the transition metal connections do not possess or only extremely small conductivenesses into preferential Lösungsmittein, it is advisable to add with difficulty reducible salts dissociating in ions aIs Leitsalze. Hiefür come in particular tetraalkyl ammonium halides or ammonium compounds with other acid residues as well as Lithiumha! ogenide in consideration. As cathodes arbitrary Meta indifferent opposite that electrolytes can! le, e.g., electrodes from A1, Hg. Pb, Sn, graphite, iron, platinum, nickel, titanium etc., to be used. It is advisable. to begin as anodes those metals, whose complex connections are to be manufactured; in this way the Herste succeeds on electro-chemical way as gross reaction for the electrolysis process! lung meta! Iorgani Komplexverbindnng from metal (begun as anode) and the complexing agent. The MetaI1 goes then proportionally to the applied quantity of electricity into solution. In many cases particularly the use of an aluminium anode worked. The production of the transition metal complexes happens in the way that solutions or Suspensioncn of connections of the transition metals in an appropriate solvent would under-stand around, after additive of a Leitsalzes, between two Meta! lelektroden, which are zweekmäßigerweise in as small a distance from about 0.2 to 5 cm as possible from each other, at temperatures between -40 and +100, preferably -20 and +50°C, to be elektrolysiert. After Dnrchgang of the computed Strornmenge kanu the formed complex connection from the reaction mixture to be then isolated. In addition, in the case of use of the transition metal complexes as catalysts the catalytic reaction can be accomplished during the electrolysis by addition of the component umzuwandeluden by the catalyst in the electrolysis cell. For example the following transition metal complexes gesture of can ground llt w in the procedure according to invention: Cyc! ooctatetraen titanch! orid z from titanium tetrachloride and Cyclooctatetraen; alI transCyc! ododecatrien (1, 5, 9) - nickel (O) - triphenylphosphin (c1 zH1 s) Ni. P (CöHs) from Nickelacety! - acetonat, Cyc! ododecatrien (2, 5, 9) and Triphenylphospin; A!! - Trans Cyc! ododecatrien (1, 5.9) - nod! (O) [(CuH1 s) Ni] from Niekelacetylacetonat and Cyclododecatrien (1, 5, 9); Until [cyc! ooctadien (1, 5)] - nod! (O) [(CsI-Ii2) 2 Ni] from Nickelacetylacetonat and Cyclooctadien (1, 5); THUS Cyclooctatetraen nod! (O) n from Nickelacetylacetouat and Cyclooctatetraen, as well as the Cyclooctatetraenmetalle of the elements iron, cobalt, chrome, molybdenum, tungsten, zircon. Further can be manufactured erfindnngsgemäfl: Kobalthaltige catalyst solutions by electrolysis of Kobaltaeetylaeetonat and Kobalt-bis [tetraäthoxy - aluminum] in THF. This solution is able butadiene in 5-Methylheptatrien or Diphenylaeetylen in Hexaphenylbenzol umzuwandein. Further procedures know NiekeI containing catalyst solutions to be received, the butadiene in Cyc by that invention would in accordance with-eat! ododecatrien (l, 0, 9) or in Cye! ooctadien and Vinyleye! ohexen transform. With electrolysis of iron (IIl) eh! orid in THF catalyst solutions, the buten (2) in Hexamethylbenzo develop! transform. The CO-free received in dern invention in accordance with-eaten procedures met all-organic complexes of ÜbergangsmetaIlen or their solutions can as catalysts for dieOIigomerisation of Olefinen and Diolefinen be used. The attempts besehriebenen in the following examples are accomplished unterAussehluß by air and humidity: B e i FR i e! 1: A solution of 12 g (46, 5 mMol) nickel (II) aeetylacetonat and 5 g Tetrabutylammoniumbromid in 100 ml THF is satisfied with butadiene and elektrolysiert with about 20°C between two aluminum electrodes with 20 cm2 of effective electrode surface and a distance each of 3 cm. Current conditions: one introduces 30 mA, V. after passage of 46, 5 m Faraday with 20°C butadiene into the electrolysis cell. After passage of altogether 200 m Faraday one distills all volatile one in the vacuum, last with 60°C/0,001 torr, into cooled days before. With the following cracking 22, 5 g became with 200 a mixture of the following Cye simmering to 110°C/15 peat in a typical attempt! ododecatrien (1, 5, 9) - Isomerer receive: trans, trans, trans: 96.5% of trans, trans, cis: 8.4% of trans, cis, cis: 0.1%. Beispie! 2: A solution of 7, 0 g (27.3 mMo!) NickeI (left) acetylacetonat, 28.6 g (109 mMoI) Triphenylphosphin and 2 g Tetrabutylammoniumbmmid in 50 ml THF is elektrolysiert with 40°C between two aluminum electrodes. Current conditions: 60 V, 40 mA with 3 cm electrode gap, applied quantity of electricity: 55 m Faraday. It results eh'le dark-brown solution, from which red-brown, glitzemde crystals fail. After filtering, washing with absolute methanol and drying one receives 28 g Nickeltetrakistriphenylphosphin. Yield: 83% of the theory. B egg s p i e 1 3: 12 g (40 mMo!) Nickel (II) acetylacetonat and 2, 5 g Tetrabutylammoniumbromid become in! 00 g Pyrtdin solved. After addition of 10 g (92, 5 mMol) Cyclooctadien (1, 5) elektrolysiert with 0°C between two electrodes from aluminum. 8trombedingnngen: 30 mA with ever 20 cmz electrode surface; ! 8 V. during the electrolysis changes the color electrolytes from blue over green after brown-yellow. After passage lemon-yellow crystals begin to fail half of the necessary quantity of electricity, after altogether 2000 mA from the solution. h with 0°C filters off and with a benzene ether solution (4: 1) to be washed and dried. The Rohprodakt is already, -, 96%ig. Yield: 7, 9 g, according to 70° [0 of the theory. Decrease in weight of the aluminium anode: 0, 72 g, according to 100% of the theory. After addition of a new quantity of Nickelacetylacetonat the Elektmlyt for a further electrolysis can be used. B eispiel 4:! 0.2 g (40 mMol) nickel (II) acetylacetonat, 3 g Tetrabutylammoniumbromid and 16 g (154 mMo!) Cyclooctatetraen become in 1! 6 g Pyridin solved and with 20°C between zweiAinminiumelektroden elektrolysiert. The Elekttolyt changes its color of blue after dark red. After passage of the quantity of electricity necessary of, ù20% fail darkly glitzemde crystals of Cyclooctatetraen niekel. After altogether 1770 mA. h are filtered the crystals with 20°C and washed with benzene. Yield: 3, 4 g according to 63% of the theory. Still further 1, g can be isolated by restricting the mother liquor. Gesamtausbeute 5, l g, according to 93% of the theory. Similar to as in example 4 when using tetrahydrofurane as solvents from iron (III) acetylacetonat to iron (O) and from Chmm (IIDacetylacetonat of trichloroethylene dicbxom received. B eispie! 5: ! 0 g (39 mMo!) Cobalt (II) acetylacetonat and 6 g Tetrabutylammoniumbromid are solved in 100 ml THF. After satisfying the solution with butadiene between two aluminum electrodes with 50 to 80 mA and 25 V one elektrolysiert. After passage of 75 m Faraday the solution in the vacuum is released from THF with 20/10.3 torr. The arrears are solved in benzene. This catalyst solution transforms butadiene with 20°C into 5-Methylheptatrien (! , 8, 6) and n-Octatrien. 13 e is p IE 1 6: Into a solution of 4, 7 g (10 mMo!) CO [A! (OCzHs) 4] s and 5 g Tetrabutylammoniumbromid in 60 ml Dimethoxyäthan during the Elektmlyse butadiene is introduced. After passage of 585 mA. h is regenerated the catalyst solution. One receives 22 g 5-Methylheptatrien with fractionated distillation (! , 3, 6). B e i s p i e 1 7:6,3 g (33 mMol) titanium (IV) chloride and 6.9 g (65.7 mMol) Cyclooctatetraen are solved in 70 ml THF and elektrolysiert between two titanium electrodes bei40°C. 8trombedingungen: a dark solution develops for 10 mA/60 V., from which dark-green crystals fail. Quantity of A: 6.3 g (17 mMol the dimeren connection). Mass-spectrometrically certain Molekulargewieht: 374. B e [s p [e 1 8 • a solution of 10, 4 g (40, 4 mMo!) Nickel (II) acetylacetonat and 1, 9 g Tetrabutylammoniumbromid in 80 mlPyridin is elektrolysiert between zweiAlumininmelektroden, after one satisfied before the electrolytes with 20°C and during the electrolysis by a moderate butadiene stream constantly satisfy hold after passage of 2580 mA. one knows h a decrease in weight of the Alumininmanode of 0,868 g, accordingly! 00% of the theory, determine. The 8trombedingungen is! 4 to 23 V and 0, 8 A/dmz electrode surface. After end of the electrolysis the mixing of functions in the vacuum fractionated desti! liert. One receives 23 g Cyclododecatrien consist (1, 5, 9), to 93,5°70 of the trans, trans, trans, to 6, 9% of Iran, Iran, cisund to 0, 3% of Iran, cis, cis connection. B e i s p i e 1 9: One proceeds as however in example 8 descriptive, used as solution center! 80 ml propylene carbonate. Current conditions. “6 to 20 V with 0, 3 A/dmz electrode surface. The liquid reaction product is with difficulty soluble in the propylene carbonate and separates as the 2nd phase above the Pmpylencarbenat phase or can with pentane or another hydrocarbon be extracted. Mixtures of cis trans isomers Cyclododecatrienen become (! , 5, 9) received: trans, trans, trans: 84°/o, trans, trans, ice: 13%, trans, cis, cis: 3%. I3 e i s p i e I 1 0: One solution of 7,9 g (30.8 mMol) nickel (II) acetylacetonat, 32, 9 g (185 mMol) Diphenylacetylen and 1.6 g Tetrabutylammoniumbromid in 80 ml THF are elektrolysiert between two aluminum electrodes with 40°C. 8trombedingungen: 45 V, 0.4 A/dmz. During the Elektmlyse those colors itself brown initially green solution. After passage of 1950 mA. h solved themselves 0.48 g aluminum from the anode, according to 68% of the theory. The solution is shifted and filtered with 50 ml diethylether. After drying the Niedemchlages 20 g become Hexaphenylbenzol (fusion point 430°C) received, d.s. 61% of the theory. Also the IR spectrum corresponds to that an authentic sample of Hexaphenylbenzol. B ice p IE! ! 1: One proceeds as descriptive in example 4, ven “ends however to steep ones of the Nickelacetylacetonats 7, 9 g (22, 5 mMo!) Iron (III) acetylaeetonat in 200 m! Pyridin, tn that 8, 4 g Lithiumch! orid as Leitsalz in place of the Tetrabutylammeniurnbromids are solved. One elektrolysiert between two aluminum electrodes with 0°C. Current conditions 30 mA with ever 80 cm2 Elektrodenfläehe. After one electrolysis duration of 61 h anodically 0.612 mg had dissolved aluminum, correspond Stromausbeute from 100%. From the dark-brown electrolytic solution one receives a brown powder after evaporation of the Pyridins with 0°C and 10-a torr; that is by Lithiumch! orid and vemnreinigtes to iron, 13 e t FR i e I 1 2 Aluminiumtris acetylaeetonat: A solution of 5, 2 g (14, 8 mMol) manganese (III) aeetylaeetonat, 6.15 g (60 mMoI) Cyclo! 0 octatetraen and! g Tetrabutylammoniumbromid in 80 ml THF is elektrolysiert with 20°C between two aluminum electrodes, Strombedingnngen80 mA/60 V. after passage of 62 m Faraday separated anodiseh 420 mg aluminum, according to an anodic Stromausbeute from 74% the dark-brown electrolyte pray 20°C released from the solvent. The rust-brown powdery arrears are extracted with warm benzene and released in such a way from Leitsalz. Yield on trichloroethylene dimangan! , 6 g (3, 8 mMol), according to 51% of the theory. With FR i el! 3: A solution of 6 g Vanadylacetylacetonat in 80 m! Tetrahydrofurane, 1, 5 g Tetrabutylammoniumbromid as Leitsalz is added to that and 4, 1 g (40 mMol) Cyc! ooctatetraen, between aluminum electrodes are elektrolysiert, current conditions 30 mA with 0, 20 dm2 each electrode surface. 40 V, temperature 0 to 5°C. The anodic Stromausbeute amounts to 65%. After evaporation of the solvent polluted lets itself to by Tetrabutylammoniumbromid [cyc! ooetatetraen] vanadinm received. 13eispiel 14: A solution of 2,0 g (7.8 mMoI) cobalt (II) acetyIacetonat in 70 ml Pyridin, in that 3, 8 g Lithiumch! orid as LeitsaIz as well as 5 g (46 mMol) Cyc! ooctadien (1, 5) and 0, 45 g (10 mMo!) Ethanol were solved, between two aluminium anodes with -5°C with 30 mA and 30 V 20 h were elektrolysiert. Anodiseh had see 0.207 g solved aluminum, according to an anodic Stromausbeute of! 00 y0. The received 28 dark-brown electrolytic solution bei-B0°C became and! 0-3 peat from Pyridin releases. The received grey powdery täickstand was extracted with 15 ml on -20°G gekühntem pentane. From the pentane excerpt 0, 82 g fell r-Cyelooctenyl-cobalt-cyc after the cooling on -80°C! ooctadien (1, 5). That corresponded to a yield of 37% of the theory. With separation anode of the cathode area by a diaphragm, for example by a porous cylindrical Tonrohr or by a glass fiber case or a filter case from Zellu! , one can do ose at Ste! le of the aluminium anodes such from Kobaltmetal! venvenden. The anodic Sttomausbeute amounts to then about 67 to 70%.