Abstract:
A plurality of metal-containing complexes of a polydentate beta-ketoiminate, one embodiment of which is represented by the structure are shown: 
     
       
                 
         
             
             
         
       
       
         
           
             wherein M is a metal such as calcium, strontium, barium, scandium, yttrium, lanthanum, titanium, zirconium, vanadium, tungsten, manganese, cobalt, iron, nickel, ruthenium, zinc, copper, palladium, platinum, iridium, rhenium, osmium; wherein R 1  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl, having from 1 to 10 carbon atoms; R 2  can be from the group consisting of hydrogen, alkyl, alkoxy, cycloaliphatic, and aryl; R 3  is linear or branched selected from the group consisting of alkylene, fluoroalkyl, cycloaliphatic, and aryl; R 4  is an alkylene bridge; R 5-6  are individually linear or branched selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, aryl, and they can be connected to form a ring containing carbon, oxygen, or nitrogen atoms; n is an integer equal to the valence of the metal M.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of Provisional U.S. Patent Application No. 60/794,820 filed Apr. 25, 2006. 
     
     BACKGROUND OF THE INVENTION 
       [0002]    The semiconductor fabrication industry continues to metal source containing precursors for chemical vapor deposition processes including atomic layer deposition for fabricating conformal metal containing films on substrates such as silicon, metal nitride, metal oxide and other metal-containing layers using these metal-containing precursors. 
       BRIEF SUMMARY OF THE INVENTION 
       [0003]    This invention is directed to metal containing polydentate β-ketoiminates and solutions wherein the polydentate β-ketoiminates incorporate nitrogen or oxygen functionality in the imino group. The polydentate β-ketoiminates are selected from the group represented by the structures: 
         [0000]    
       
                 
         
             
             
         
       
     
         [0004]    wherein M is a metal having a valence of from 2 to 5. Examples of metals include calcium, strontium, barium, scandium, yttrium, lanthanum, titanium, zirconium, vanadium, tungsten, manganese, cobalt, iron, nickel, ruthenium, zinc, copper, palladium, platinum, iridium, rhenium, and osmium. A variety of organo groups may be employed as for example wherein R 1  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl, having from 1 to 10 carbon atoms, preferably a group containing 1 to 6 carbon atoms; R 2  is selected from the group consisting of hydrogen, alkyl, alkoxy, cycloaliphatic, and aryl; R 3  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl; R 4  is an alkylene bridge, preferably a group containing 2 or 3 carbon atoms, thus making a five- or six-membered coordinating ring to the metal center; R 5-6  are individually selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, aryl, and they can be connected to form a ring containing carbon, oxygen, or nitrogen atoms. The subscript n is an integer and equals the valence of the metal M. 
         [0000]    
       
                 
         
             
             
         
       
     
         [0005]    wherein M is a metal ion selected from Group 4, 5 metals including titanium, zirconium, and hafnium; wherein R 1  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl, preferably a group containing 1 to 6 carbon atoms; R 2  is selected from the group consisting of hydrogen, alkyl, alkoxy, cycloaliphatic, and aryl; R 3  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl; R 4  is an alkylene bridge, preferably a group containing 2 or 3 carbon atoms, thus making a five- or six-membered coordinating ring to the metal center; R 5-6  are individually selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, aryl, and they can be connected to form a ring containing carbon, oxygen, or nitrogen atoms; R 7  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl; wherein m and n are at least 1 and the sum of m+n is equal to the valence of the metal. 
         [0000]    
       
                 
         
             
             
         
       
     
         [0006]    wherein M is an alkaline earth metal with specific examples including calcium, strontium, barium; R 1  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl, preferably a group containing 1 to 6 carbon atoms; R 2  is selected from the group consisting of hydrogen, alkyl, alkoxy, cycloaliphatic, and aryl; R 3  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl; R 4-5  are each a 2 carbon atom alkylene bridge, thus making a five-membered coordinating ring to the metal center; R 6-7  are individually selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, aryl, or they can be connected to form a ring containing carbon, oxygen, or nitrogen atoms; and X is either an oxygen, or a nitrogen substituted with a hydrogen, an alkyl or an aryl group. 
         [0007]    Several advantages can be achieved through these metal-containing polydentate β-ketoiminates as precursors for chemical vapor deposition or atomic layer deposition, and these include:
       an ability to form reactive complexes in good yield;   an ability to form monomeric complexes, particularly strontium and barium complexes, coordinated with one kind of ligand, thus allowing one to achieve a high vapor pressure;   an ability to produce highly conformal metal thin films suited for use in a wide variety of electrical applications;   an ability to form highly conformal metal oxide thin films suited for use in microelectronic devices;   an ability to enhance the surface reaction between the metal-containing polydentate β-ketoiminates and the surface of a substrate due to the high chemical reactivity of the complexes; and,   an ability to tune the physical property of these metal-containing polydentate β-ketoiminates via a change in the R 1-7  groups.       
 
     
     
       DETAILED DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a drawing representative of the crystal structure of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium. 
           [0015]      FIG. 2  is a TGA diagram of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium, indicating the complex is volatile but decomposes at higher temperature. 
           [0016]      FIG. 3  is a drawing representing the crystal structure of tris(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)ytterium. 
           [0017]      FIG. 4  is a drawing representative of the crystal structure of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)cobalt. 
           [0018]      FIG. 5  is a drawing representative of the crystal structure of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)nickel. 
           [0019]      FIG. 6  is a drawing representative of the crystal structure of tris(tert-butoxy( )(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV). 
           [0020]      FIG. 7  is a TGA diagram of tris(tert-butoxy)(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV), indicating the complex is volatile with less than 2% residue. 
           [0021]      FIG. 8  is a drawing representing the crystal structure of bis(2,2-dimethyl-5-(2-(2-(dimethylamino-ethyl)(methylamino))ethyl-imino)-3-hexanonato)barium. 
           [0022]      FIG. 9  is a TGA/DSC diagram of the TGA/DSC of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium before (dashed line) and after (solid line) dissolving in NMP, suggesting that bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium and NMP are compatible. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    This invention is related to metal-containing polydentate β-ketoiminate precursors and their solutions which are useful for fabricating conformal metal containing films on substrates such as silicon, metal nitride, metal oxide and other metal layers via deposition processes, e.g., CVD and ALD. Such conformal metal containing films have applications ranging from computer chips, optical device, magnetic information storage, to metallic catalyst coated on a supporting material. In contrast to prior polydentate β-ketoiminate precursors, the polydentate β-ketoiminate ligands incorporate at least one amino organo imino functionality which is in contrast to the literatures reported alkoxy group as the donating ligand. 
         [0024]    Oxidizing agents for vapor deposition process include oxygen, hydrogen peroxide and ozone and reducing agents for deposition processes include hydrogen, hydrazine, monoalkylhydrazine, dialkylhydrazine, and ammonia. 
         [0025]    One type of structure in the metal precursor is illustrated in structure 1A below where the metal M has a valence of 2 having the formula: 
         [0000]    
       
                 
         
             
             
         
       
     
         [0026]    wherein M is selected from group 2, 8, 9, 10 metal atoms. In this precursor it is preferred that R 1  is a C 1-10  alkyl group, preferably a t-butyl or t-pentyl group when the metal is strontium and barium and C 1-5  when cobalt or nickel, R 2  and R 3  are methyl groups R 5  and R 6  are individually lower C 1-3 , preferably methyl groups and R 4  is a C 2-3  alkylene bridge, preferably an ethylene group. Preferred metals are calcium, strontium, barium, iron, cobalt, and nickel. 
         [0027]    Another type of structure within the first class of metal complexes containing polydentate β-ketoiminate ligands is illustrated in structure  2 A below where the metal M has a valence of 3 having the formula: 
         [0000]    
       
                 
         
             
             
         
       
     
         [0028]    wherein M is selected from group 3 metal atoms. In this precursor it is preferred that R 1  is a C 4-6  alkyl group, preferably a t-butyl and t-pentyl group, R 2  and R 3  are methyl groups, R 5  and R 6  are individually lower C 1-3  alkyl, preferably methyl groups, and R 4  is a C 2-3  alkylene bridge, preferably an ethylene group. Preferred metals are scandium, yttrium, and lanthanum. 
         [0029]    The second class of metal-containing precursors are comprised of polydentate β-ketoiminate ligands as shown in formula B: 
         [0000]    
       
                 
         
             
             
         
       
     
         [0030]    wherein M is a Group 4 or 5 metal such as titanium, zirconium, or hafnium. As shown the complex consists of at least one alkoxy ligand and a polydentate β-ketoiminato ligand having at least one amino organo imino. The preferred R 1-6  groups are the same as in formula A. The preferred R 7  group is a linear or branched alkyl, e.g., iso-propyl, butyl, sec-butyl, and tert-butyl, m and n are at least 1 and the sum of m+n is equal to the valence of the metal 
         [0031]    The last class of metal-containing polydentate β-ketoiminate precursors are shown in formula C: 
         [0000]    
       
                 
         
             
             
         
       
     
         [0032]    wherein M is an alkaline earth metal wherein R 1  is selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, and aryl, having from 1 to 10 carbon atoms; R 2-3  are individually selected from the group consisting of hydrogen, alkyl, alkoxy, cycloaliphatic, and aryl; R 4-5  are individually C 2-3  alkylene bridges, preferably ethylene groups, R 6-7  are individually selected from the group consisting of alkyl, fluoroalkyl, cycloaliphatic, aryl, and heterocyclic containing a oxygen, or nitrogen atom; X is either an oxygen, or nitrogen substituted with a hydrogen, an alkyl or an aryl group. 
         [0033]    The polydentate β-ketoiminate ligands can be prepared by well known procedure such as the Claisen condensation of a bulky ketone and an ethyl ester in presence of a strong base such as sodium amide or hydride, followed by another known procedure such as Schiff base condensation reaction with alkylaminoalkylamine. 
         [0000]    
       
                 
         
             
             
         
       
     
         [0034]    The ligands can be purified via vacuum distillation for a liquid or crystallization for solid. 
         [0035]    As a preferred method for the formation of high yield polydentate ligands, it is preferred to choose a bulky R 1  group, e.g., C 4-10  alkyl groups without hydrogen attached to the carbon connected to the ketone functionality, most preferred R 1  group is tert-butyl or tert-pentyl. The R 1  group prevents side reactions occurring in the following Schiff condensation and later protecting the metal centers from inter-molecular interaction. There is a competing issue and that is that the R 1-7  groups in the polydentate ligands should be as small as possible in order to decrease the molecular weight of the resulting metal-containing complexes and allow the achievement of complexes having a high vapor pressure. The preferred R 4-5  groups contain 2 to 3 carbon atoms in order to make the resulting complexes more stable via forming a five- or six-membered coordinating ring to the metal center. 
         [0036]    The metal-containing complexes can then be prepared via the reaction of the resulting tridentate ligands with pure metal, metal amide, metal hydride, and metal alkoxide. The metal-containing complexes can also be prepared via reacting the polydentate ligand with alkyl lithium or potassium hydride to provide the lithium or potassium salt of the ligand, then followed by reaction with metal halide, MX 2  (X═Cl, Br, I). The group 4 and 5 mixed ligand complexes can be made via changing the ratio of metal alkoxide to the polydentate ligands. 
         [0000]    
       
                 
         
             
             
         
       
       
                 
         
             
             
         
       
     
         [0037]    These metal-containing complexes with polydentate β-ketoiminate ligands can be employed as potential precursors to make thin metal or metal oxide films via either the chemical vapor deposition (CVD) or atomic layer deposition (ALD) method at temperatures less than 500° C. The CVD process can be carried out with or without reducing or oxidizing agents whereas an ALD process usually involves the employment of another reactant such as a reducing agent or oxidizing agent. 
         [0038]    For multi-component metal oxide, these complexes can be premixed if they have the same polydentate β-ketoiminate ligands. These metal-containing complexes with polydentate β-ketoiminate ligands can be delivered in vapor phase into a CVD or ALD reactor via well-known bubbling or vapor draw techniques. A direct liquid delivery method can also be employed by dissolving the complexes in a suitable solvent or a solvent mixture to prepare a solution with a molar concentration from 0.001 to 2 M depending the solvent or mixed-solvents employed. 
         [0039]    The solvent employed in solubilizing the precursor for use in a deposition process may comprise any compatible solvent or their mixture including aliphatic hydrocarbons, aromatic hydrocarbons, ethers, esters, nitrites, and alcohols. The solvent component of the solution preferably comprises a solvent selected from the group consisting of glyme solvents having from 1 to 20 ethoxy —(C 2 H 4 O)— repeat units; C 2 -C 12  alkanols, organic ethers selected from the group consisting of dialkyl ethers comprising C 1 -C 6  alkyl moieties, C 4 -C 8  cyclic ethers; C 12 -C 60  crown O 4 -O 20  ethers wherein the prefixed C i  range is the number i of carbon atoms in the ether compound and the suffixed O i  range is the number i of oxygen atoms in the ether compound; C 6 -C 12  aliphatic hydrocarbons; C 6 -C 18  aromatic hydrocarbons; organic esters; organic amines, polyamines and organic amides. 
         [0040]    Another class of solvents that offers advantages is the organic amide class of the form RCONR′R″ wherein R and R′ are alkyl having from 1-10 carbon atoms and they can be connected to form a cyclic group (CH 2 ) n , wherein n is from 4-6, preferably 5, and R″ is selected from alkyl having from 1 to 4 carbon atoms and cycloalkyl. N-methyl and N-cyclohexyl 2-pyrrolidinones are examples. 
         [0041]    The following example illustrates the preparation of the metal-containing complexes with polydentate β-ketoiminate ligands as well as their use as precursors in metal-containing film deposition processes. 
       EXAMPLE 1 
     Synthesis of 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone 
       [0042]    In a 500 mL Schlenk flask, 29.3 g (206 mmol) of 2,2-dimethyl-3,5-hexanedione and 24 g (170 mmol) anhydrous Na 2 SO 4  were loaded with 200 mL THF. To the flask, 20.08 g (228 mmol) 3-(dimethylamino)ethylamine in 20 mL of THF was dropwise added. The reaction mixture was stirred for three days. Upon completion, the GC/MS analysis of the reaction mixture indicated the reaction was complete with trace amount 3-(dimethylamino)ethylamine. All volatiles were removed by distillation at temperature below 130° C. Subsequently the resulting slight yellow solution was vacuum distilled via a short-path apparatus. Crystallization from hexanes provided about 36 g of a white crystal with a yield of 82%. GC analysis of the crystals dissolved in hexane only shows one observable GC peak besides the hexane. The solid crystals were found to have a melting point of 28-30° C. 
         [0043]      1 H NMR (500 MHz, C 6 D 6 ): δ=11.30 (s, 1H, C(O)CHC(NH)), 5.15 (s, 1H, C(O)CHC(NH)), 2.80 (m, 2H, HNCH 2 CH 2 N(CH 3 ) 2 ), 2.05 (t, 2H, HNCH 2 CH 2 N(CH 3 ) 2 ), 1.95 (s, 6H, N(CH 3 ) 2 ), 1.50 (s, 3H, C(NH)CH 3 ), 1.35 (s, 9H, C(CH 3 ) 3 ). 
       EXAMPLE 2 
     Synthesis of 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanone 
       [0044]    In a procedure analogously to 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone, starting with 2,2-dimethylhexa-3,5-dione (5.07 g, 36 mmol), Na 2 SO 4  (3.5 g, 24.66 mmol), and 3-(diethylamino)ethylamine (5.25 g, 45 mmol). An orange/yellow liquid was obtained via a short-path vacuum distillation apparatus after removal of all volatiles. The yield is 78%. 
         [0045]      1 H NMR (500 MHz, C 6 D 6 ): δ=11.27 (s, 1H, C(O)CHC(NH)), 5.16 (s, 1H, C(O)CHC(NH)), 2.82 (m, 2H, HNCH 2 CH 2 N(CH 2 CH 3 ) 2 ), 2.26 (q, 4H, N(CH 2 CH 3 ) 2 ), 2.20 (t, 2H, HNCH 2 CH 2 N(CH 2 CH 3 ) 2 ), 1.55 (s, 3H), 1.25 (s, 9H, C(CH 3 ) 3 ), 0.86 (t, 6H, N(CH 2 CH 3 ) 2 ). 
       EXAMPLE 3 
     Synthesis of 2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanone 
       [0046]    In a procedure analogously to 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone, starting with 2,2-dimethylhexa-3,5-dione (19.27 g, 136 mmol), Na 2 SO 4  (13 g, 92 mmol), and 3-(dimethylamino)propylamine (15.72 g, 154 mmol). A yellow liquid was obtained via a short-path vacuum distillation apparatus after removal of all volatiles. The yield is 89%. 
         [0047]      1 H NMR (500 MHz, C 6 D 6 ): δ=11.30 (s, 1H, C(O)CHC(NH)), 5.17 (s, 1H, C(O)CHC(NH)), 2.84 (q, 2H, HNCH 2 CH 2 N(CH 3 ) 2 ), 2.05 (t, 2H, HNCH 2 CH 2 CH 2 N(CH 3 ) 2 ), 1.94 (s, 6H, N(CH 3 ) 2 ), 1.54 (s, 3H, C(NH)CH 3 ), 1.32 (m, 2H, HNCH 2 CH 2 CH 2 N(CH 3 ) 2 ), 1.27 (s, 9H, C(CH 3 ) 3 ). 
       EXAMPLE 4 
     Synthesis of 2,2-dimethyl-5-(diethylaminopropyl-imino)-3-hexanone 
       [0048]    In a procedure analogously to 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone, starting with starting with 2,2-dimethylhexa-3,5-dione (3.50 g, 25 mmol), Na 2 SO 4  (4.81 g, 34 mmol), and 3-(dimethylamino)propylamine (3.57 g, 27 mmol). The resulting light yellow/green liquid was vacuum distilled via a short-path apparatus to provide a yield of 67%. 
         [0049]      1 H NMR (500 MHz, C 6 D 6 ): δ=11.41 (s, 1H, C(O)CHC(NH)), 5.17 (s, 1H, C(O)CHC(NH)), 2.84 (q, 2H, HNCH 2 CH 2 N(CH 3 ) 2 ), 2.28 (q, 4H, N(CH 2 CH 3 ) 2 ), 2.19 (t, 2H, HNCH 2 CH 2 CH 2 N(CH 2 CH 3 ) 2 ), 1.53 (s, 3H, C(NH)CH 3 ), 1.33 (m, 2H, HNCH 2 CH 2 CH 2 N(CH 2 CH 3 ) 2 ), 1.28 (s, 9H, C(CH 3 ) 3 ), 0.86 (t, 6H, N(CH 2 CH 3 ) 2 ). 
       EXAMPLE 5 
     Synthesis of 4-(dimethylaminoethyl-imino)-2-pentanone 
       [0050]    In a procedure analogously to 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone, starting with starting with 2,4-pentadione (8.00 g, 80.7 mmol), Na 2 SO 4  (14 g, 98.64 mmol), and 3-(dimethylamino)ethylamine (7.83 g, 88.8 mmol). A green liquid was obtained via vacuum distillation at an oil bath of 95-105° C. under 150 mTorr. The yield was 83%. GC analysis indicated one peak. 
         [0051]      1 H NMR (500 MHz, C 6 D 6 ): δ=11.11(br, s, 1H, C(O)CHC(NH)), 4.88 (s, 1H, C(O)CHC(NH)), 2.78 (m, 2H, HNCH 2 CH 2 N(CH 3 ) 2 ), 2.01 (t, 3H, HNCH 2 CH 2 N(CH 3 ) 2 ), 2.00 (s, 3H, C(O)CH 3 ), 1.93 (s, 6H, N(CH 3 ) 2 ), 1.47 (s, 3H, C(NH)CH 3 ). 
       EXAMPLE 6 
     Synthesis of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium 
       [0052]    40.0 g (0.066 mol) of Sr(N(SiMe 3 ) 2 ) 2 .2THF was loaded in a 500 mL Schlenk flask with 100 ml THF. To this flask was dropwise added 29.0 g (0.14 mol) wax-like 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone in 100 mL of THF. The resulting light yellow clear solution was stirred at room temperature over night. All volatiles were then removed under vacuum to give a yellow solid which was dissolved in 100 mL of hot hexanes. GC/MS analysis of the trapped volatile liquid indicated it contains THF and by-product hexamethylsilylamine. GC/MS of the yellow solid dissolving in THF revealed there is only 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone besides THF, suggesting the solid contains the tridentate β-ketoiminate ligand. The hexanes solution was then concentrated to about 30 mL to precipitate white crystals on the bottom. The flask was kept at −20° C. to afford more colorless crystals. 26.1 g of the crystals was collected and dried under vacuum. The yield is 77% on the basis of strontium. 
         [0053]    Elemental analysis: calcd for C 24 H 46 N 4 O 2 Sr: C, 56.49; N, 10.98; H, 9.09. Found: C, 56.34; N, 11.32; H, 8.91.  1 H NMR (500 MHz, C 6 D 6 ): δ=5.16 (s, 2H), 2.97 (t, 4H), 2.26 (b, 4H), 1.89 (s, 12H), 1.77 (s, 6H), 1.37 (s, 18H). 
         [0054]    A colorless crystal of bis(2,2-dimethyl-5-((dimethylaminoethylene)imino)-3-hexanonato)strontium was structurally characterized by X-ray single crystal analysis (see  FIG. 1 ). The structure below shows strontium is coordinated with two 2,2-dimethyl-5-(dimethylamino)ethylene)imino)-3-hexanonato ligands in a distorted octahedral environment. The Sr—N distances range from 2.614 to 2.690 Å and the average Sr—O is 2.353 Å.  FIG. 2  exhibits a TGA diagram of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′) strontium, indicating the complex is volatile but decomposes at higher temperature. 
       EXAMPLE 7 
     Synthesis of bis(2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium 
       [0055]    In a procedure analogously to example 6, starting with Sr(N(SiMe 3 ) 2 ) 2 .2THF (2.66 g, 0.005 mol) and 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanone (2.0 g, 0.008 mol). 1.91 g of the crystals was collected and dried under vacuum after removal of all volatiles and work-up. The yield is 84% on the basis of strontium. 
         [0056]    Elemental analysis: calcd for C 28 H 54 N 4 O 2 Sr: C, 59.38; N, 9.89; H, 9.61. Found: C, 58.99; N, 9.90; H, 9.51.  1 H NMR (500 MHz, C 6 D 6 ): δ=5.14 (s, 2H), 2.11 (t, 4H), 2.67 (b, 4H), 2.54 (b, 8), 1.76 (s, 6H), 1.36 (s, 18H), 0.74 (t, 12H). 
         [0057]    A colorless crystal of bis(2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanonato)strontium was structurally characterized by X-ray single crystal analysis. The structure below shows strontium is coordinated with two 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanonato ligands in a distorted octahedral environment. The Sr—N distances range from 2.604 to 2.677 Å and the average Sr—O is 2.374 Å. 
       EXAMPLE 8 
     Synthesis of tris(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)yttrium 
       [0058]    In a procedure analogously to example 6, starting with Y(N(SiMe 3 ) 2 ) 3  (2.00 g, 3.9 mmol)) and 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone (2.41 g, 11.35 mmol). 1.57 g of white solid was collected and the yield is 57% on the basis of yttrium. 
         [0059]    Elemental analysis: calcd for C 36 H 69 N 6 O 3 Y: C, 59.81; N, 9.63; H, 11.63. Found: C, 59.81; N, 9.37; H, 11.83.  1 H NMR (500 MHz, C 6 D 6 ): d=5.14 (s, 3H), 3.47 (t, 6H), 2.49 (t, 6H), 2.22 (s, 18H), 1.81 (s, 9H), 1.27 (s, 27H). 
         [0060]    A colorless crystal of tris(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)yttrium was structurally characterized by X-ray single crystal analysis (see  FIG. 3 ), revealing that the yttrium atom is coordinated with three 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato ligands. 
       EXAMPLE 9 
     Synthesis of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)cobalt 
       [0061]    Procedures (a) and (b) are shown for producing this compound. (a) 2 g (0.015 mol) of anhydrous CoCl 2  was loaded in a 500 mL Schlenk flask with 30 ml THF. To this flask was added (2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)Li prepared in situ by the reaction of 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone (6.4 g, 0.03 mol) with a 2.5 M LiBu n  hexane solution (12 mL, 0.03 mol) in 40 mL of hexanes at −78° and stirred at room temperature for 30 min. The mixture was stirred at room temperature over night. After the reaction was complete, all volatiles were then removed under vacuum to give rise to a dark brown solid. Extraction and filtration produced a dark brown solution and brown solid. The brown was LiCl contaminated with trace amount of Co compounds. The brown solution was then dried at 50° C. to yield a dark brown solid. Sublimation of the dark brown solid at 105° C. and 50 Torr provide greenish brown microcrystals. The yield is 50% on the basis of cobalt. 
         [0062]    Elemental Analysis for CoC 24 H 46 N 4 O 2 : C, 59.86; N, 11.63; H, 9.63. Found: C, 59.73; N, 11.62; H, 9.77.  1 H NMR (500 MHz, C 6 D 6 ): δ=119.04, 25.38, 11.86, 3.42, 1.36, 0.43, −16.00, −97.00. 
         [0063]    Procedure (b) A single crystal of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato) cobalt was characterized by X-ray single crystal analysis (see  FIG. 4 ), exhibiting that the cobalt atom is coordinated with two 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanonato ligands in a distorted octahedral environment. 
         [0064]    (b). NaH (0.34 g, 14 mmol) was slowly added to a solution of 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanone (2.07 g, 12 mmol) in 70 mL of THF. After bubbling ceased, CoCl 2  (1.07 g, 8 mmol) was added to reaction flask. 2.25 g of brown crystals were collected after workup and the yield was 69%. 
       EXAMPLE 10 
     Synthesis of bis(2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanonato)cobalt 
       [0065]    In a procedure similar to example 9, starting with 2,2-dimethyl-5-(dimethylaminopropylene-imino)-3-hexanone (1.50 g, 0.007 mol) and (0.22 g, 0.009 mol) NaH (0.22 g, 0.009 mol), CoCl 2  (0.38 g, 0.003 mol) was added. Following workup, the orange crystals were obtained by sublimation of the resulting brown solid. The yield is 82%. 
         [0066]    Elemental Analysis for CoC 26 H 50 N 4 O 2 : C, 61.27; N, 10.99; H, 9.89. Found: C, 61.42; N, 11.19; H, 9.43.  1 H NMR (500 MHz, C 6 D 6 ): δ=14.40, 8.83, 1.42, −1.45, −5.54, −21.49, −31.91. 
         [0067]    A single crystal of bis(2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanonato) cobalt was characterized by X-ray single crystal analysis, exhibiting that the cobalt atom is coordinated with two 2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanonato ligands in an octahedral environment. 
       EXAMPLE 11 
     Synthesis of bis(4-(dimethylaminoethyl-imino)-2-hexenonato)cobalt 
       [0068]    In a procedure similar to example 9, starting with (2.07 g, 0.012 mol) 4-(dimethylaminoethyl-imino)-2-hexenone (2.07 g, 0.012 mol) and (0.34 g, 0.14 mol) NaH, followed by addition of CoCl 2  (1.07 g, 0.008 mol) was added. Crystals were grown from a hexane solution and the yield is 69%. 
         [0069]    Elemental Analysis for CoC 18 H 34 N 4 O 2 : C, 54.40; N, 14.83; H, 8.62. Found: C, 54.72; N, 14.04; H, 10.10.  1 H NMR (500 MHz, C 6 D 6 ): δ=25.47, 17.44, 8.69, 1.35, −9.47, −12.00, −21.40, −116.00, 120.04. 
       EXAMPLE 12 
     Synthesis of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)nickel 
       [0070]    In a procedure similar to example 9, starting with (3.48 g, 0.016 mol) 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone (3.48 g, 0.016 mol) and 2.5M butyl lithium (6.5 mL, 0.016 mol), followed by addition of NiCl 2  (1.02 g, 0.008 mol) was added. Upon sublimation the bright green solid was obtained with a yield of 66%. 
         [0071]    Elemental Analysis for NiC 24 H 46 N 4 O 2 : C, 59.89; N, 11.63; H, 9.63. Found: C, 60.80; N, 11.62; H, 8.80. 
         [0072]    A single crystal of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato) nickel was characterized by X-ray single crystal analysis (see  FIG. 5 ), exhibiting that the nickel atom is coordinated with two 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato ligands in an octahedral environment. 
       EXAMPLE 13 
     Synthesis of bis(2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanonato)nickel 
       [0073]    In a procedure similar to example 9, starting with 2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanone (3.66 g, 0.016 mol) and 2.5M butyl lithium (6.3 mL, 0.015 mol) followed by addition of NiCl 2  (1.01 g, 0.008 mol) was added. Green crystals were harvested from hexane solution. 
         [0074]    Elemental Analysis for NiC 26 H 50 N 4 O 2 : C, 61.30; N, 11.52; H, 9.89. Found: C, 61.52; N, 11.06; H, 9.34.  1 H NMR (500 MHz, C 6 D 6 ): δ=60.00, 36.56, 3.57, 1.47, −2.84, 14.70, 16.10, −76.00. 
         [0075]    A single crystal of bis(2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanonato) nickel was characterized by X-ray single crystal analysis, exhibiting that the nickel atom is coordinated with two (2,2-dimethyl-5-(dimethylaminopropyl-imino)-3-hexanonato) ligands in an octahedral environment. 
       EXAMPLE 14 
     Synthesis of bis(4-(dimethylaminoethyl-imino)-2-hexanonato)nickel 
       [0076]    In a procedure similar to Example 9, starting with 4-(dimethylaminoethyl-imino)-2-hexanone (2.15 g, 0.013 mol) and NaH (0.36 g, 0.015 mol), and NiCl 2  (0.74 g, 0.006 mol) was added. The product was sublimed and crystallized from hexane. Yield is 74%. 
         [0077]    Elemental Analysis for NiC 18 H 34 N 4 O 2 : C, 54.43; N, 14.10; H, 8.63. Found: C, 54.21; N, 14.04; H, 10.10. 
       EXAMPLE 15 
     Synthesis of tris(isopropoxy)(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)titanium(IV) 
       [0078]    Ti (OCH(CH3)2)4(2.00 g, 0.007 mol), (1.45 g, 0.007 mol) 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone(1.45 g, 0.007 mol), and 15 mL hexane were loaded into a 100 mL Schlenk flask. The mixture was stirred at 40° C. for 16 hours. Under vacuum all volatiles were removed, and the yellow powdery solid was washed with hexane and dried. Sublimation provides the light green crystals with a yield of 90%. 
         [0079]      1 H NMR (500 MHz, C 6 D 6 ): δ=5.18 (s, 1H), s, 1H), 5.00 (b, 3H), 2.96 (s, 2H), 2.48 (s, 6H), 2.28 (t, 2H), 1.53 (s, 3H), 1.35 (s, 9H), 1.30 (s, 18H). 
       EXAMPLE 16 
     Synthesis of tris(isopropoxy)(4-(dimethylaminoethyl-imino)-2-hexenonato)titanium 
       [0080]    In a procedure similar to Example 15, stirring (2.08 g, 0.007 mol) Ti (OCH(CH 3 ) 2 ) 4  and (1.19 g, 0.007 mol) 5-(dimethylaminoethyl-imino)-3-hexanonato. Sublimation of the sticky yellow solid produced light green crystals, yielding 74%. 
         [0081]    Elemental Analysis for C 18 H 38 N 2 O 4 Ti: C, 54.82; N, 9.71; H, 7.10. Found: C, 52.50; N, 9.50; H, 7.39.  1 H NMR (500 MHz, C 6 D 6 ): δ=4.92 (b, 3H) 4.83 (s, 1H), 2.96 (s, 2H), 2.47(s, 6H), 2.27 (t, 2H), 1.95 (s, 3H), 1.45 (s, 6H), 1.30 (s, 18H). 
         [0082]    A single crystal of tris(isopropoxy)(4-(dimethylaminoethyl-imino)-3-hexanonato)titanium was characterized by X-ray single crystal analysis, exhibiting that the Titanium atom was coordinated with three isopropoxy groups and one 5-(dimethylaminoethyl-imino)-3-hexanonato ligand. 
       EXAMPLE 17 
     Synthesis of tris(tert-butoxy)(4-(dimethylaminoethyl-imino)-2-hexanonato)hafnium(IV) 
       [0083]    In a procedure similar to Example 15, starting with Hf(OC(CH 3 ) 3 ) 4  (2.73 g, 0.006 mol) and 5-(dimethylaminoethyl-imino)-3-hexanone (1.01 g, 0.005 mol). Volatiles were examined via GC/MS, and 2-methyl-2-propanol was observed. The white solid was collected with a yield of 95%. Crystallization from pentane/hexane solution provides colorless block-like crystals. 
         [0084]      1 H NMR (500 MHz, C 6 D 6 ): δ=4.81 (s, 1H), 2.89 (t, 2H), 2.44 (s, 8H), 1.55 (s, 9H), 1.42 (s, 3H), 1.36 (s, 18H) 
       EXAMPLE 18 
     Synthesis of tris(tert-butoxy)(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)zirconium(IV) 
       [0085]    In a procedure similar to Example 15, starting with Zr(OC(CH 3 ) 3 ) 4  (1.81 g, 0.005 mol) and 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanone ((1.05 g, 0.005 mol). Workup provided a light yellow solid with a yield of 95%. 
         [0086]      1 H NMR (500 MHz, C 6 D 6 ): δ=4.86 (s, 1H, BuCOCHCN), 2.91 (b, t, 2H, NCH 2 CH 2 NMe 2 ), 2.39 (b, s, 6H, CH 2 N(CH 3 ) 2 ), 2.39 (b, t, 2H, NCH 2 CH 2 NMe 2 ), 1.55 (s, 9H, (CH 3 ) 3 CCO), 1.49 (s, 3H, COCHCN(CH 3 )), 1.31 (s, 27H, (OC(CH 3 ) 3 ) 
         [0087]    A colorless crystal of tris(tert-butoxy)(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)zirconium(IV) was characterized by X-ray single crystal analysis, exhibiting that the zirconium atom was coordinated with three tert-butoxy groups and one substituted 2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato ligand. 
       EXAMPLE 19 
     Synthesis of tris(tert-butoxy)(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV) 
       [0088]    In a procedure similar to Example 15, stirring (2.2 g, 0.006 mol) Zr(OC(CH 3 ) 3 ) 4  (2.2 g, 0.006 mol) and 5-(dimethylaminoethyl-imino)-3-hexanone (1.0 g, 0.006 mol) in THF produced a light yellow solid with a yield of 82% upon workup. 
         [0089]      1 H NMR (500 MHz, C 6 D 6 ): δ=4.86 (s, 1H, CH 3 COChCN), 2.90 (s, 2H, NCH 2 CH 2 NMe 2 ), 2.36 (b, s, 6H, CH 2 N(CH 3 ) 2 ), 2.36 (b, t, 2H, NCH 2 CH 2 NMe 2 ), 1.89 (s, 3H, CH 3 COCHCN), 1.51 (s, 9H, CH 3 (CH 3 ) 2 )COCH), 1.41 (s, 3H, CH 3 COCHCNCH 3 ), 1.35 (s, 18H, (CH 3 ) 2 (CH 3 )COCH) 
         [0090]    A colorless crystal of tris(tert-butoxy( )(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV) was characterized by X-ray single crystal analysis (see  FIG. 6 ), exhibiting that the zirconium atom was coordinated with three tert-butoxy groups and one substituted 4-(dimethylaminoethyl-imino)-2-hexanonato ligand.  FIG. 7  reveals that a TGA diagram of tris(tert-butoxy)(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV), indicating the complex is volatile with less than 2% residue. 
       EXAMPLE 20 
     Synthesis of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato)barium 
       [0091]    In a procedure analogously to example 6, starting with Ba(N(SiMe 3 ) 2 ) 2 .2THF and 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanone. A very viscous orange oil was obtained upon removal of all volatiles. NMR indicates there are some unreacted 2,2-dimethyl-5-(diethylaminoethyl-imino)-3-hexanone. The free ligand was removed via a short-path distillation to provide an orange solid. 
         [0092]      1 H NMR (500 MHz, C 6 D 6 ): δ=5.11 (br, s), 3.10 (br, s), 2.21 (br, s), 1.95 (br, s), 1.80 (s, 6H), 1.38 (s). 
       EXAMPLE 21 
     Synthesis of tetrakis(ethoxy)(4-(dimethylaminoethyl-imino)-2-hexanonato)tantalum(V) 
       [0093]    2,2-dimethyl-(5-(dimethylamino)propyl-imino)-3-hexenone (0.64 g, 3.8 mmol) was slowly added a flask Loaded with Ta 2 (OEt) 10  (1.50 g, 1.85 mmol) to added. The flask was heated to 80° C. for 3 hours and then the by-product ethanol was removed under vacuum to yield 1.6 g of clear orange liquid. The yield is 1.6 g, 98%. 
         [0094]      1 H NMR (500 MHz, C 6 D 6 ): δ=4.79 (s, 1H), 4.76 (q, 2H), 4.71 (q, 2H), 4.31 (q, 2H), 4.28 (q, 2H), 3.74 (t, 2H), 2.60 (t, 2H), 2.13 (s, 6H), 1.85 (s, 3H), 1.70 (s, 3H), 1.40 (t, 3H), 1.38 (t, 3H), 1.20 (t, 6H). 
       EXAMPLE 22 
     Synthesis of 2,2-dimethyl-5-(2-(2-(dimethylamino)ethoxy)ethyl-imino)-3-hexanone 
       [0095]    In a 100 mL round bottom flask equipped with a magnetic stirrer, 8 g 2,2-dimethylhexane-3,5-dione was combined with 1.1 equivalents of 2-(2-(dimethylamino)ethoxy)ethylamine, anhydrous sodium sulfate and anhydrous diethyl ether and stirred over three days under nitrogen. The ether was removed on a rotary evaporator and the residue was vacuum distilled through a Vigreux column to yield 9.7 g of product. 
         [0096]      1 H NMR: (300 MHz, THF d8 ): δ=11.05 (s, 1H), 5.06 (s, 1H), 3.51 (t, 2H), 3.50 (t, 2H), 3.37 (q, 2H), 2.42 (t, 2H), 2.17 (s, 6H), 1.92 (s, 3H), 1.05 (s, 9H). 
       EXAMPLE 23 
     Synthesis of bis(2,2-dimethyl-5-(2-(2-(dimethylamino)ethoxy)ethyl-imino)-3-hexanonato)barium 
       [0097]    In a 100 mL Schlenk flask with magnetic stirrer, in a glove box, 1.25 g sublimed barium metal was combined with 3.15 g 2,2-dimethyl-5-(2-(2-(dimethylamino)ethoxy)ethyl-imino)-3-hexanone and 30 mL anhydrous THF. The flask was placed on a Schlenk line and fitted with a cold finger condenser. Anhydrous ammonia was allowed to condense into the flask and refluxed with the cold finger condenser for 4 hours. The flask and condenser were allowed to warm up to room temperature over night and the ammonia was allowed to escape through a gas bubbler. The cloudy amber solution was filtered through celite and the product was crystallized from hot hexanes as white crystals. 
         [0098]      1 H NMR: (300 MHz, THF d8 ): δ=4.64 (s, 1H), 3.94 (t, 2H), 3.71 (t, 2H), 3.51 (t, 2H), 2.49 (t, 2H), 2.18 (s, 6H), 1.78 (s, 3H), 1.10 (s, 9H). 
       EXAMPLE 24 
     Synthesis of 2,2-dimethyl-5-(2-(2-(dimethylamino-ethyl)(methylamino))ethyl-imino)-3-hexanone 
       [0099]    in a 100 mL round bottom flask equipped with a magnetic stirrer, 1.9 g 2,2-dimethylhexane-3,5-dione was combined with 1.1 equivalents of 2-(2-(dimethylamino-ethyl)(methylamino))ethylamine, anhydrous sodium sulfate and anhydrous diethyl ether and stirred over night under nitrogen. The ether was removed on a rotary evaporator and the residue was vacuum distilled through a Vigreux column to yield 2.7 g of product. 
         [0100]      1 H NMR: (300 MHz, THFd 8 ): δ=10.99 (s, 1H), 5.06 (s, 1H), 3.28 (Q, 2H), 2.53 (t, 2H), 2.48 (t, 2H), 2.37 (t, 2H), 2.25 (s, 3H), 2.15 (s, 6H), 1.92 (s, 3H), 1.06 (s, 9H). 
       EXAMPLE 25 
     Synthesis of bis(2,2-dimethyl-5-(2-(2-(dimethylamino-ethyl)(methylamino))ethyl-imino)-3-hexanonato)barium 
       [0101]    In a 50 mL Schlenk flask with magnetic stirrer, in a glove box, 1.05 g sublimed barium metal was combined with 2.72 g 2,2-dimethyl-5-(2-(2-(dimethylamino-ethyl)(methylamino))ethyl-imino)-3-hexanone and 20 mL anhydrous THF. The flask was placed on a Schlenk line and fitted with a cold finger condenser. Anhydrous ammonia was allowed to condense into the flask and refluxed with the cold finger condenser for 4 hours. The flask and condenser were allowed to warm up to room temperature over night and the ammonia was allowed to escape through a gas bubbler. The cloudy grayish suspension was concentrated, suspended in hot hexanes and filtered through celite. The product was recrystallized from hot hexanes several times to give 0.4 g product as colorless crystals. 
         [0102]    Elemental analysis: calcd for C 30 H 60 BaN 6 O 2 : C, 53.45; N, 12.47; H, 8.97. Found: C, 53.33; N, 12.71; H, 9.44.  1 H NMR (500 MHz, C 6 D 6 ): δ=5.07(s, 1H), 3.28 (br, s, 2H), 2.49 (very br, 6H), 2.23 (s, 6H), 2.22 (sh, 3H), 1.84 (s, 3H), 1.40 (s, 9H). 
         [0103]    A single crystal of bis(2,2-dimethyl-5-(2-(2-(dimethylamino-ethyl)(methylamino))ethyl-imino)-3-hexanonato)barium was characterized by X-ray single crystal analysis, exhibiting that the barium atom is coordinated with two 2,2-dimethyl-5-(2-(2-(dimethylamino-ethyl)(methylamino))ethyl-imino)-3-hexanonato ligands in tetradentate fashion. 
       EXAMPLE 26 
     Preparation of 1M solution of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium in N-methyl-2-pyrrolidinone 
       [0104]    To 1 ml vial containing 0.25 g of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium, 0.49 ml of N-methyl-2-pyrrolidinone (NMP) was added to result in a pale yellow clear solution. The solution was kept at room temperature over night and then dried under vacuum to give a pale yellow solid.  FIG. 9  shows the TGA/DSC of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium before and after dissolving in NMP, suggesting that bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium and NMP are compatible and the resulting solution can be used in CVD or ALD processes. 
       EXAMPLE 27 
     Preparation of 1.0M solution of bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium in N-cyclohexyl-2-pyrrolidinone 
       [0105]    0.19 mL N-cyclohexyl-2-pyrrolidinone was added to a 2 mL vial containing bis(2,2-dimethyl-5-(dimethylaminoethyl-imino)-3-hexanonato-N,O,N′)strontium (0.10 g, 0.20 mmol) to result in a light green clear solution. TGA of the solution indicates the mixture is volatile. 
       EXAMPLE 28 
     Preparation of 0.9M solution of tris(isopropoxy)(4-(dimethylaminoethyl-imino)-2-hexenonato)titanium in N-methyl-2-pyrrolidinone 
       [0106]    0.27 mL N-methyl-2-pyrrolidinone was added to a 2 mL vial containing tris(isopropoxy)(4-(dimethylaminoethyl-imino)-2-hexenonato)titanium (0.1 g, 0.25 mmol) to result in a bright orange solution. TGA of the solution indicates the mixture is volatile. 
       EXAMPLE 29 
     Preparation of 0.75M solution of tris(tert-butoxy( )(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV) in N-methyl-2-pyrrolidinone 
       [0107]    0.28 mL N-methyl-2-pyrrolidinone was added to a 2 mL vial containing tris(tert-butoxy( )(4-(dimethylaminoethyl-imino)-2-hexanonato)zirconium(IV) (0.10 g, 0.21 mmol) to result in a greenish yellow solution. TGA of the solution indicates the mixture is volatile.