Processes for producing transition metal amido and imido compounds
View Patent ↗Processes are provided for producing transition metal amidos and/or imidos. In methods according to this invention, at least one halogenated transition metal, an amine compound and a solvent are combined, followed by the addition of an alkylated metal or a Grignard reagent to produce the transition metal amide and/or imido.
1. A method for producing a transition metal amido and/or imido comprising (i) combining in a first reaction mixture at least one halogenated transition metal, an amine composition, and a solvent, (ii) subsequently adding to at least a portion of the first reaction mixture an alkylated metal or a Grignard reagent thereby forming a second reaction mixture, and (iii) subjecting the second reaction mixture to reaction conditions sufficient to produce the transition metal amido and/or imido, wherein the amine composition comprises at least one primary amine, at least one secondary amine, at least one diamine, or mixtures thereof.
2. A one-pot method for producing a transition metal amido and/or imido comprising (i) combining in a first reaction mixture at least one halogenated transition metal, an amine composition, and a solvent, (ii) subsequently adding an alkylated metal or a Grignard reagent to the first reaction mixture, and (iii) following the addition of the alkylated metal or a Grignard reagent to the first reaction mixture, subjecting the first reaction mixture to reaction conditions sufficient to produce the transition metal amido and/or imido, wherein the amine composition comprises at least one primary amine, at least one secondary amine, at least one diamine, or mixtures thereof.
3. A method of producing a transition metal amido and/or imido, comprising (i) combining at least one halogenated transition metal, an amine composition, and a solvent to produce a first intermediate composition, (ii) optionally removing an amine hydrohalide from the first intermediate composition, (iii) combining a portion of the first intermediate composition and an alkylated metal or a Grignard reagent to produce a second intermediate composition, and (iv) combining at least a portion of the second intermediate composition and an alkylated metal or the Grignard reagent to produce the transition metal amido and/or imido, wherein the amine composition comprises at least one primary amine, at least one secondary amine, at least one diamine, or mixtures thereof.
4. The method of claim 1 wherein the transition metal is hafnium, titanium, tantalum, or zirconium, and the halogen is chlorine, bromine, or iodine.
5. The method of claim 1 wherein the halogenated transition metal has the formula M 1 X 1 n , where M 1 is a transition metal atom and X 1 is independently a halogen atom, a cyclopentadienyl, an indenyl, a fluorenyl, an alcohol, or a substituted phenol, provided that at least one X 1 is a halogen atom, and n is the valence of M 1 .
6. The method of claim 1 any of the preceding claims wherein the amine compound comprises one or more hydrocarbyl groups having from 1 to about 20 carbon atoms.
7. The method of claim 1 wherein the alkylated metal has the formula M 2 R 3 or M 2 R 3 2 wherein M 2 is a non-transition metal in Groups 1 or 2 , and R 3 is a hydrocarbyl group having 1 to about 20 carbon atoms.
8. The method of claim 1 wherein the Grignard reagent is an alkyl or aryl magnesium halide having the formula R 4 MgX 2 wherein R 4 is an alkyl or aryl group having from 1 to about 20 carbon atoms, Mg is magnesium, and X 2 is a halogen atom.
9. The method of claim 1 wherein a molar excess of amine compound with respect to transition metal halide is employed.
10. The method of claim 1 wherein the temperature of step (i) is no higher than about 40° C.
11. The method of claim 1 wherein the temperature subsequent to and during the addition of the alkylated metal or Grignard reagent is maintained below about ambient temperature.
12. The method of claim 1 wherein after the addition of the alkylated metal or Grignard reagent is complete, the reaction mixture is allowed to increase under constant mixing, which is maintained for from about 30 min to about 24 hours.