GB896391A - Organometallic compounds - Google Patents

Abstract

Arene metal compounds of formula AMQ(Y)n where M is a central metal atom, having an atomic number of from 7 to 14 less than that of the next higher rare gas of atomic number 36, 54 or 86, A is an arene molecule co-ordinately linked to the metal by donation of 6 electrons, Q is at least one dissimilar electron donating group linked to said metal atom, each of which group or groups donates 1 to 8 electrons to the metal so that the electronic configuration of the said metal is equal to or not more than two less than the electronic configuration of the next higher rare gas, Y is an anion and n is 0-3 may be used as fuel additives, e.g. for gasoline. The metal may be titanium, zirconium, hafnium from Group IVa, vanadium, niobium, tantalum from Group Va, chromium, molybdenum, tungsten from Group VIa, manganese, technetium, rhenium from Group VIIa, iron, nithenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum from Group VIII and copper, silver and gold from Group Ib. Numerous compounds are specified.ALSO:Arene metal compounds of formula AMQ(Y)n where M is a central metal atom having an atomic number of from 7 to 14 less than that of the next higher rare gas of atomic number 36, 54 or p 86, A is an arene molecule co-ordinately linked to the metal by donation of six electrons, Q is at least one dissimilar electron donating group linked to said metal atom, each of which group or groups donates 1 to 8 electrons to the metal so that the electronic configuration of the said metal is equal to or not more than two less than the electronic configuration of the next higher rare gas, Y is an anion and n is 0-3, may be used as catalysts in the polymerization of olefines. The preferred metal is titanium: others are zirconium, hafnium from Group IVa, vanadium, niobium, tantalum from Group Va, chromium, molybdenum, tungsten from Group VIa, manganese, technetium, rhenium from Group VIIa, iron, nithenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum from Group VIII and copper, silver and gold from Group Ib. The compounds may be employed with aluminium and aluminium halides.ALSO:The invention comprises compounds of formula AMQ(Y)n wherein M is a central metal atom having an atomic number of from 7 to 14 less than that of the next higher rare gas of atomic number 36, 54 or 86, A is an arene molecule coordinately linked to the metal by donation of 6 electrons, Q is at least one dissimilar electron donating group linked to said metal atom, each of which group or groups donates 1 to 8 electrons to the metal so that the electronic configuration of the said metal is equal to or not more than two less than the electronic configuration of the next higher rare gas, Y is an anion and n is 0-3. The metal may be titanium, zirconium, hafnium from Group IV(a), vanadium, niobium, tantalum from Group V(a), chromium, molybdenum, tungsten from Group VI(a), manganese, technetium, rhenium from Group VII(a), iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum from Group VIII and copper, silver and gold from Group I(b). The arene molecule is preferably a mononuclear hydrocarbon containing 6-18 carbon atoms such as benzene, toluene, mesitylene, ethylbenzene and tetramethylbenzene, but polynuclear hydrocarbons (naphthalene) and substituted hydrocarbons (chlorobenzene, anisole) may be used. The residue AMQ may be ionic, in which case the anion Y may be a halide, cyanide, nitrate or other inorganic or organic ion. A long list of electron donating groups (Q) grouped according to the number of electrons donated, is included in the specification. The compounds of the invention may be prepared (a) by preparing a diarene metal complex and replacing one arene molecule by an electron donating group or groups, (b) by introducing an arene molecule in coordinate covalent bonding into a metal coordination compound such as a metal carbonyl, thus mesitylene is reacted with bromomanganese pentacarbonyl in the presence of aluminium chloride, hydrolysing the product and saturating with KI to give mesitylene manganese tricarbonyl iodide, (c) by introducing a metal compound into an arene molecule either directly or by means of a phenyl Grignard reagent or an aryl metal compound, thus treating a cyclopentadienyl manganese compound with excess phenyl Grignard and hydrolysing to give benzene manganese cyclopentadienyl, or (d) by reacting a metal compound-frequently an inorganic compound-with an arene hydrocarbon in the presence of a Lewis acid material and of the dissimilar electron donor thus, reacting molybdenum bromide with benzene and carbon monoxide in the presence of aluminium bromide to give benzene molybdenum tricarbonyl bromide: if desired the metal and arene hydrocarbon may be reacted together in a first step and the so-formed complex reacted with a source of the dissimilar electron donor, or a compound of the metal which contains the dissimilar electron donor group may be reacted with the desired arene molecule in the presence of the Lewis acid catalyst, thus chloromanganese pentacarbonyl may be reacted with toluene in the presence of aluminium chloride to produce toluene manganese tricarbonyl chloride. The reaction may be carried out in an inert solvent such as an ether, polyether, acetal or tertiary amine; examples specified include dimethyl ether, methyl isopropyl ether, ethylene glycol diethers, dioxane and tetrahydrofuran, (a) arene metal dicarbonyl compounds may be prepared by pyrolysis of a compound containing the arene metal tricarbonyl cation in the presence of an excess of alkali metal or alkaline earth metal cyanide, preferably in a polar solvent, thus mesitylene manganese tricarbonyl iodide is reacted in boiling water with KCN to give mesitylene cyano-manganese dicarbonyl. The compounds of the invention may be used as polymerization catalysts in olefin polymerization (see Group IV(a)), as drying agents and as fuel additives (see Group III).