DE2536162A1 - Coordinate diphosphine polymers for catalyst prepn. - by reacting alkaline diphosphine alcoholate and halogenated polymer in two stages - Google Patents

Abstract

Coordinate diphosphine polymers useful as catalysts, e.g. in hydroformylation, carbonylation and carboxylation, and oligomerisation and hydrogenation of mono- and diolefines, are prepd. by (a) adding a soln. of (I) an alkaline diphosphine alcoholate to a suspension of (II) a halogenated polymer in (III) a liquid (b) reacting the mixt. to ambient temp. for 2-24 pref. 4-8 hrs., (c) completing the reaction at an elevated temp. up to the reflux temp. for 0.5-6 pref. 1-3 hrs., and (d) reacting the formed coordinate diphosphine polymer with a transition metal cpd. The catalyst is insoluble in reaction mixts., easily recovered from reaction mixts., has long catalytic life. high selectively; wide range of catalysts is obtainable.

Description

"New polymeric diphosphine ligands and their metalated derivatives".

The invention relates to new polymeric ligands containing a diphosphine contain. The invention includes the preparation of these ligands and their use for the representation of various transition metal complexes; it concerns in the same Way also the newly obtained complexes.

We currently know the great importance that the catalysts as Complexes of transition metals have in which the ligands, the two the metal surrounding electrons are comparable groups, but they are based on a polymer Chain to be grafted on.

The catalysts of this type offer a number of advantages over the classical homogeneous systems which consist of a metal ion which is generally surrounded by several donor ligands L which donate two electrons and which have the general formula can be represented.

The main advantages can be approached: Insolubility in the reaction medium, or ease of separation from the reaction mixture; longer Lifetime of the catalyst effect because the secondary reactions are blocked. the possibility of the selectivity of the reaction due to the presence of certain forms to change which are preferred by the carrier of the polymer. Among these catalytic Systems are known in which the ligand is grafted onto a polymer Phosphine represents, resulting in a complex containing only one monophosphine leads.

However, only then do certain homogeneous catalytic reactions take place starting when a diphosphine is coordinated to the metal ion that is the seat of the catalytic Represents reaction. This is the case, for example, with the dimerigation-functionalization reaction of butadiene, in the codimerization reaction butadiene-ethylene or in the hydrogenation of «-olefins.

Therefore, it was important to find catalytic complexes that contained the Have advantages of these two types of catalysts, that is, catalysts in which a diphosphine coordinated to a metal ion simultaneously on a chain polymer is grafted on.

Our attempts to do this now have access to these novel ones Complexes result from simple procedures that are readily available from Starting materials go out, whereby one first the synthesis of polymeric diphosphine complexes and then performing the metalation of these polymers. The new polymers Diphosphine complexes and their metalated derivatives, which can be obtained by classical reactions between the polymeric diphosphine complex and a transition metal compound, are characterized in that they can be achieved by implementing a in an alkali metal alcoholate of a diphosphine and dissolved in a suitable solvent represents a halogenated polymer suspended in a suitable liquid.

This reaction can be illustrated in the following general notation: The alkali alcoholate of diphosphine, represented in the above equation as MaO (P2), can also be written in a more detailed way as follows: Here, Ma means an alkali metal such as lithium, sodium or potassium; n can have values between 1 and 4. When n = 1, the alcoholate can be obtained by the action of diphenylphosphine alkali metal Ph2P-Ma on epichlorohydrin. This reaction is described in the literature, Chem.Ber. 1963, 96, 407) after the treatment with hydroxy-bis-diphenylphosphine, the first reaction step leads to the intermediate stage of the alcoholate, which can be isolated.

The halogenated polymer or resin (Pol hal) that is used in the process of the present invention, consists of a carbon skeleton, which is very variable in its type: a polyvinyl frame, a polybutadiene - or a polystyrene framework. The halogen bound to the polymer can be chlorine, bromine or Be iodine; However, for reasons of cost, preference will be given to using chlorinated polymers. A particularly preferred group of resins is that of the chloromethylated polystyrenes, what in further text using the symbolic notation (PS) CH2 C1 is expressed; the latter can be networked at the beginning. The networking will by copolymerizing styrene with different amounts of divinylbenzene causes: the products obtained in this way are on the market under different trademarks available.

The incorporation rate of divinylbenzene is between 0.25% and 10%, but preferably between 0.5% and 4%, to in the chloromethylated product to have relatively easy access to the halogenated sites, which is good Implementation with the relatively voluminous reactant MO (P2) allowed. The rate of chloromethylation is between 1 and 25%, but preferably between 5% and 20%. High chloromethylation rates necessarily result in networking. The rate of crosslinking and the rate of chloromethylation ultimately influence the catalytic activity in the reaction under investigation of the polymeric ligand.

The implementation of the halogenated resin with the alcoholate MaO (P2) runs in a solvent that does not react with this alcoholate: it can be the same solvent as that in which the alcoholate is obtained, or not all of them protic and non-halogenated solvents such as aromatic hydrocarbons (Benzene, toluene)) cyclic hydrocarbons (cyclohexane), aliphatic hydrocarbons (Hexane), ether (tetrahydrofuran, dioxane, dimethoxyethane). The implementation is preferably running at normal temperature, with a residence time between 2 and 24 hours, preferably between 1 and 8 hours, preferably constant at 6 hours, then at increased Temperature, going up to the reflux temperature of the reaction mixture and the residence time can be 0.5 to 6 hours, preferably 1 to 3 hours.

We have been able to establish that the reaction leads to the formation of the ether Pole O (P2) according to equation (1) runs faster if the halogen of the pole (hal) Iodine is. A special form of invention based on the speed of formation of ether (Pol) O (P2) is based, consists in the alcoholate MaO (P2) in a suitable Solvent with the product of the metathetic exchange reaction between the to use halogenated resin and an alkali iodide when this resin is chlorinated or is brominated. A halogen-iodine exchange takes place in the course of this reaction.

In those cases where this exchange of the chlorine or iodine radical Performing first through the iodine radical, the halogenated resin is in the appropriate Solvent with a 10 to 100% excess of iodine alkali (LiJ, NaJ, KJ, RbJ, CsJ) - based on the stoichiometric amount - brought to reaction; the reaction time extends here to a period of 2 to 24 hours, preferably from 2 to 6 hours, with the reaction temperature between 200 C and 1000 C, preferably between 200 ° C and 500 ° C.

From the reaction scheme of equation (1) it can be seen that the amount of alcoholate MaO (P2) used is a function of the halogen content of the halogenated polymers, and our research has shown that the use an excess of alcoholate does not bring about any appreciable improvement.

Another, special and preferred embodiment of the present invention Invention allows the preparation of the polymeric diphosphine ligand in a single Step without separating the intermediates by doing all the reactions in the same Reactor executes. This implementation is special interesting in the case where the alcoholate is obtained from epichlorohydrin.

In this procedure, the alkali compound of the diphenylphosphine itself is first produced in the reaction vessel using methods known per se, for example by the action of diphenylchlorophosphine on an alkali metal in a suitable solvent, according to the general equation: As suitable solvents, those described above can be used. Preferred solvents are the ethers (especially dioxane). When the first reaction has ended, the stoichiometric amount of epichlorohydrin, dissolved in the same solvent, is added to the reaction medium. While the alkali metal alcoholate of the diphosphine is forming, the halogenated resin or its reaction product with an alkali iodide suspended in a suitable solvent which is generally the same as that used in the two previous reaction steps is added to the reaction mixture.

The reaction is carried out under the conditions described. The reaction mixture is then concentrated. The diphosphine polymer is isolated through Precipitation with solvents, preferably methanol.

The diphosphine polymer thus obtained is obtained as a powder; it can Metals are deposited, which are able to coordinate complexes with compounds of trivalent phosphorus. These metals are mainly those of the groups IV to VIII and group Ib of the periodic table, in particular that of group VIII. Titanium, vanadium, chromium, manganese, iron, cobalt, nickel, ruthenium, Rhodium, palladium, iridium and platinum.

These complexes are formed by being in a suitable Solvent and at a certain temperature, which is generally around 500 C, converts the diphosphine polymers obtained, be it with the salts MtXn of the transition metals mentioned above, be it with complexes of these transition metal salts LmMtXn or with complexes of these transition metals in a lower oxidation state LpMtXq The ligands L are donor ligands with two free electrons that easily like carbon monoxide, strongly polarized solvents (alphatic and aromatic nitriles, sulfoxides), olefins, diolefins, amines and phosphines. the Ligands X are donor ligands with one electron, such as halides and pseudohalides, Carboxylates and alcoholates. Certain ligands can also be of the LX type, such as Allyl, l'titrosyl and acetylacetonate ligands. The indices m, n, p and q are integer and lie between 0 and 6 and their sums m + n and p + q are smaller or equal to 6. So one can use these transition metal compounds without the the following list is a limitation, list: TiCl4, FeCl2, CoCl2, NiCl2, Zr (OBu) 4, Pd (OAc) 2, (PhCN) 2 PdCl2, (Me2SO) 4 NiCl2, (PhCN) 2 PtCl2, V (CO) 6, Cr (CO) 6, Mn2 (CO) 10, Fe (CO) 5, Fex (CO) q, C02 (CO) 8, Ni (CO) 4, Ni (COD) 2, Ni (acetonitrile) 2, (C3H5NiBr) 2, Mo (CO) 6, (Ru (CO) 2Cl2) 2, (Ph3P) 4Pd (Ph3P) 2Pd (maleic anhydride), RhCl (PPh3) 3, (Rh (CO) 2Cl) 2, W (CO) 6, Re (CO) 1O, JrCl (CO) (PPh3) 2, Pt (PPh3) 3.

A suitable solvent is understood to mean one that the reacts neither with dembine nor with the other of the two reactants, but that at least partially solves one of the two.

In general, the polymeric diphosphine is used in finely divided form Form suspended in a liquid one that does not dissolve the polymer, but that does is a solvent for the metal compound defined above. These solvents can be aliphatic and aromatic hydrocarbons or ethers and alcohols. The metal compound is added to the suspension and the reaction mixture is stirred until the metal compound has reacted with the polymeric diphosphine. The duration of this Implementation and the temperature at which it is carried out are two factors which affect the rate of incorporation of the metal ion into the polymer. The presence an excess of the metal compound has only a secondary influence.

In certain cases it is preferable to react on two different ones Temperatures to carry out, especially if the metallic derivative is two different Undergoes transformations.

It is known, for example, that with C02 (CO) 8 in a first step the action of a phosphorous ligand L the compound CCo (CO) 4) 4) gGo (CO) 42 supplies, from which, through the loss of carbon monoxide, Co2 (CO) 7L etc. is formed. Temperatures between 0 and 100 C are generally comfortable, but one draws but reaction temperatures between 20 and 600 C before.

The dwell time can be between 0.5 and 72 hours, mostly depending on the situation on the reaction temperature. If you work at normal temperature, you pull in generally a reaction time between 2 and 24 hours before. An increase in Temperature generally shortens this period, as it causes the cleavage of certain substances unstable ligands from the metal compound facilitated.

Since some metal compounds are sensitive to oxygen and to The reactions are generally carried out under an inert gas atmosphere carried out using argon or nitrogen as the inert gas.

The metalated polymers obtained in this way can be used as catalysts various already described, carried out by means of homogeneous catalysts Reactions are used.

Therefore one can use the polymers metallized with Co, Ni, Rh or Pd, to catalyze hydroformylation, carbonylation or carboxylation reactions, the derivatives of Fe, Co, Ni and Pd to carry out oligomerization reactions of the mono- and To catalyze diolefins, the derivatives of Fe, Co, Pd and Pt finally in the hydrogenation of olefins and diolefins.

The efficiency of the new complexes of the present invention in A given reaction depends on the choice of metal and the experimental one Condition.

The following examples illustrate the possibilities of the present Invention without, however, limiting it.

B e i s p i e 1 1: Representation of a polymeric diphosphine in several Stages.

To a suspension of Ph2RK 2 dioxane (50 mM) in 250 ml of absolute Ether is added dropwise to a solution of 2.3 g at 0 ° C. under an argon atmosphere (50 mM) freshly distilled epichlorohydrin in 25 ml of absolute ether. After The reaction mixture is discolored and stirred for an additional hour at 250.degree the potassium chloride formed is filtered off. The filtrate is a suspension of chloromethylated polystyrene with a chlorine content of 16% (5 g) in 100 ml of tolnol admitted. To Two hours of contact at 250 C is heated one Hour to 500 ° C. and then the reaction volume is reduced to 50 ml in vacuo. 200 ml of methanol are then added in order to precipitate the polymer and then washed 5 times with 20 ml of methanol each time and then 5 more times with 20 ml of petroleum ether each time. So 6.8 g of a polymer are obtained which contain 6.9% phosphorus and traces of chlorine. The theoretical maximum phosphorus content is 7.8%.

B e i s p i e 1 2: Representation of a polymeric diphosphine without isolation of intermediate products: To a suspension of potassium (0.2 at.g.) in 200 ml of dry A solution of 22.05 is added dropwise to dioxane at 500 ° C. under an argon atmosphere g (100 mM) chlorodiphenylphosphine in 50 ml of dioxane are added. After all Ph2PCl has been added is, the mixture is stirred for one hour at 1000 C and then the solution is cooled to about 100 C. A solution of 50 mM epichlorohydrin in 25 ml of dioxane is then added dropwise and stir after the addition for another hour at 250 C. Then add a solution of chloromethylated polystyrene (chlorine content: 5.5% (10 g) in 50 ml Dioxane is added and two more hours at 25 ° C and one hour at 50 ° C.

The reaction mixture is concentrated to 50 ml and mixed with 250 ml of methanol treated; the precipitate is filtered, 5 times with 20 ml of methanol each time and five times washed with 20 ml of petroleum ether each time. This gives 10.3 g of a polymer which is 1.95 % Phosphorus and traces of chlorine. The theoretical maximum content of phosphorus is 2.7% Example 1 e 3 - 5: These examples follow the same procedure how in the previous example for the grand location show that the presence of a excess of phosphorus reagent has only a weak influence on the phosphorus content of the polymer.

Example Yield of poly-phosphorus used.

KPPh2 (mM) mers (g) (%) 2 50 10.3 1.95 3 100 10 2.30 4 150 9.95 2.25 5 25 9.6 1.70 Example 1 6: This example shows that the exchange of Chlorine by iodine in the chloromethylated polystyrene reduces the residence time and the slightly increased final phosphorus content of the polymer.

To a solution of the alcoholate (KO (P2), shown according to the procedure According to Example 1, a suspension of chloromethylated polystyrene (chlorine content 5.5% (5 g) in 100 ml of dioxane, which was previously mixed with 10 g of potassium iodide for two hours has been. The reaction mixture is stirred for two hours at room temperature and subsequently worked up as described above. 6.2 g of a polymer are obtained which contains 2.35% phosphorus.

B e i s p i e 1 7: To a solution of alcoholate, which according to example 1 is prepared, a suspension of polymer Merrifield Fluka is added, one Polystyrene crosslinked with 2% divinylbenzene and chloromethylene with 2.5% (5 g) in Dioxane (50 ml). The mixture is stirred at 250 ° C. for 2 hours, then at 500 ° C. for 2 hours The reaction mixture treated above leads to 5.2 g of a polymer containing 1.2% phosphorus contains. The theoretical maximum content of phosphorus is 1.22%.

Example 1 e 8-10: Polymers with cobalt (II) A suspension of the phosphine polymer derived from chloromethylated polystyrene (phosphorus content 2% (2.5 g) in 50 ml of methanol are mixed with a solution of x mM dry cobalt chloride in lOx ml of methanol. After one hour at 500 ° C., the precipitate is filtered off and washed five times with 10 ml of methanol each time. After drying, a pale blue color is obtained Product with varying cobalt content depending on the amount of cobalt chloride used.

Example x (mM) Yield (g) Co (%) 8 10 2.55 0.28 9 25 2.60 0.58 10 50 2.55 0.22 Examples 1 e 11 - 13: Polymers with nickel (II) A suspension 2.5 g of the same phosphine polymer in 50 ml of ethanol are mixed with a solution of x mM nickel chloride in 10x ml of ethanol. After one hour at 500 ° C., it is filtered off and the precipitate was washed 5 times with 10 ml of ethanol each time. Receives after drying you get a pale pink product with varying depending on the amount of nickel chloride used Nickel content.

Example X (mM) Yield (g) Ni (%) 11 10 2.50 o, 38 12 25 2.55 0.53 13 50 2.60 0.42 Example 1 14: Polymer with palladium (II) A suspension of 2.5 g of the same phosphine polymer in 50 ml of benzene is with a solution of 10 mM bis (benzonitrile) palladium dichloride in 20 ml of benzene were added. Stir 48 Hours at room temperature, then the reaction mixture is concentrated in vacuo to about half a, 100 ml of methanol are added and the precipitate is filtered off away; it is washed five times with 10 ml of methanol each time and five times with 10 ml of hexane each time. To after drying, 2.7 g of a light brown polymer with a palladium content are obtained of 3.75%.

EXAMPLE 1 15: Polymer with Rhodium (I) A suspension of 2.5 g of the same phosphine polymer in 50 ml of benzene is mixed with a solution under argon of 2 mM dichlorotetracarbonyldirhodium (I) in 20 ml of benzene. One stirs 72 Hours at room temperature, the reaction mixture is reduced to half in vacuo a, 100 ml of methanol is added and the precipitate is filtered off. It is washed five times with 10 ml of methanol each time and five times with 10 ml of hexane. After drying 2.45 g of a red-brown polymer with a rhodium content of 6.8% are obtained. The JR spectrum of the product shows CO bands at 2075 and 1985 cm 1, where the latter bond is extraordinarily strong.

EXAMPLE 1 16: Polymer with Cobalt (O) A suspension of 2.5 g of the same phosphine polymer in 50 ml of benzene is mixed with a solution under argon of 10 mM dicobalt octacarbonyl in 20 ml of benzene. The mixture is stirred for 4 hours Room temperature and two hours at 600 O C. The reaction mixture is then concentrated in vacuo and treated with 100 ml of hexane. The precipitate formed is filtered off, washed five times with 10 ml of hexane each time and five times with 10 ml of ether each time. After drying, 2.8 g of polymer with a cobalt content of about 5.8 are obtained %. The JR spectrum of the product shows CO bands at 2080, 2060 and 1960 cm 1 on, the latter band being extraordinarily strong.

At s p i e 1 17: Polymeres mit Nickel (o) A suspension of phosphine polymers (Phosphorus content 1.5% (2.5 g) in 50 ml of benzene is mixed with a solution under argon of 10 mM nickel tetracarbonyl in 20 ml of benzene. First stir four Hours at room temperature and then two hours at 40 ° C. Then the reaction mixture evaporated in vacuo and treated with 100 ml of hexane. The precipitate formed is filtered, washed five times with 10 ml of hexane each time and five times with 10 ml of ether each time. After drying, 2.5 g of a light gray polymer with a nickel content are obtained of about 1.96%. The JR spectrum of the product shows bands at 2070, 1955 as well l940 cm.

Claims (13)

Patent claims: 1. Process for the preparation of polymeric diphosphine ligands and their metalated derivatives, which are obtained by reactions of classical Type between the polymeric diphosphine ligand and a compound of a transition metal, characterized in that an alkali metal alcoholate of a diphosphine is in solution in a solvent and a halogenated polymer in suspension in one Lets the liquid react that the reaction is preferably first carried out at room temperature for a period between two and 24 hours and preferably between 4 and Carries out 8 hours and then at a temperature up to the reflux temperature of the reaction mixture for a period of between 0.5 and 6 hours and preferably can go between 1 and 3 hours. 2. The method according to claim 1, characterized in that the alkali alcoholate has a formula of the type where Ma is an alkali metal such as lithium, sodium, potassium and n can assume values from 1 to 4. 3. The method according to claim 2, characterized in that if n is equal to 1, the alkali metal alcoholate is obtained from epichlorohydrin. 4. The method according to claim 1, characterized in that the halogenated Polymers has a polyvinyl, polybutadiene or polystyrene skeleton and the halogen has chlorine, bromine or preferably iodine. 5. The method according to claim 1 and 4, characterized in that the halogenated iodinated polymers in situ through a methatic exchange reaction between the halogenated resin (chlorinated or brominated) and an excess of 10 to 100% of an alkali iodide during the reaction of the alkali alcoholate with the halogenated polymers is obtained. 6. The method according to claim 1, characterized in that the solvent in which one dissolves the alkali metal alcoholate of the diphosphine, as well as the liquid in which the polymer is suspended, non-protic and non-halogenated, such as aromatic alicyclic and aliphatic hydrocarbons and ethers 7. The method according to claim 1 characterized in that the polymeric diphosphine ligand in a single operation is obtained from halodiphenylphosphine without neither the alkaline diphenylphosphine, still to separate the alkali metal alcoholate of the diphosphine. 8. The method according to claim 1, characterized in that the metallated derivatives by reacting the polymeric diphosphines with salts of transition metals or complexes of these salts in which the transition metal may be a weak Has an oxidation stage at a temperature of about 500 C in a solvent manufactures. 9. The method according to claim 9, characterized in that the implementation carried out at two consecutive temperatures will, while the metal derivative undergoes two successive transformations. 10. New polymeric ligands of polymeric diphosphines as well as theirs metalated derivatives of corresponding transition metals, characterized in that that by reacting the alkali metal alcoholate dissolved in a solvent Diphosphine and a halogenated polymer suspended in a liquid be prepared according to the method described in claims 1 to 9. 11. New polymeric diphosphine ligand, characterized in that it is made from diphenylphosphine potassium, epichlorohydrin and chloromethylated polystyrene will be produced. i2. New polymeric diphosphine ligand, characterized in that he without separating the intermediate products through continuous further processing of the Reaction mixture in dioxane of chlorodiphenylphosphine, potassium epichlorohydrin is produced in dioxane and chloromethylated polystyrene. 13. New metalated compounds that differ from the polymeric ligands derive, characterized in that they contain cobalt, nickel, palladium and rhodium contain.