A heterogeneous synthesis method of cyclopentadienyl metal precursor

Abstract

The present invention discloses a heterogeneous synthesis method of a cyclopentadienyl metal precursor, which belongs to the technical field of semiconductor deposition materials. The structure of the cyclopentadienyl metal precursor is represented by R z CpM(NR x R y )3, wherein M is selected from Ti, Zr, Hf, Cp is a cyclopentadienyl group, R, R x and R y Independently selected from C1-C5 alkyl, z is an integer of 0-5; The heterogeneous synthesis method comprises the following steps: after dialkyl amido lithium, metal halide and heterogeneous reaction catalyst are mixed and reacted, cyclopentadiene monomer is added to react. The present application, by citing a specific heterogeneous reaction catalyst and optimizing reaction condition parameters such as raw material equivalent ratio, material addition sequence, reaction temperature and reaction time, can effectively improve reaction yield and product quality, well overcome the defects of low yield and unstable process in traditional heterogeneous synthesis route, and can be applied to the industrial production and manufacturing of cyclopentadienyl titanium / zirconium / hafnium precursors.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor deposition materials, and particularly relates to a heterogeneous synthesis method of a cyclopentadienyl metal precursor. Background Art

[0002] Oxide films of Group IVB metals exhibit high dielectric (i.e., high-k) properties and are widely used in logic chips, memory chips, and other semiconductor components, offering an ideal alternative to traditional silicon dioxide films. However, the use of precursor materials for preparing Group IVB metal oxide films in CVD / ALD processes presents a number of challenges. For example, metal chloride precursors (e.g., HfCl₄ and ZrCl₄) produce HCl as a byproduct, leading to equipment corrosion and reduced film purity. Tetrakis(dialkylamino)metal precursors (e.g., Hf(NMe₂)₄ and Zr(NEtMe)₄) readily condense at low temperatures, resulting in poor precursor utilization and reduced process repeatability. Furthermore, some precursors exhibit insufficient reactivity at low temperatures, making them incompatible with the ALD process requirements for flexible electronic devices.

[0003] Tris(dialkylamino)cyclopentadienyl metal precursors such as CpZr(NMe2)3, CpZr(NMeEt)3, CpTi(NMe2)3, CpHf(NMe2)3, CpHf(NMeEt)3, etc. not only have good stability and high vapor pressure, but also show quite high reactivity. They are one of the best choices for preparing high-K films. They can stably form high-quality metal element-containing films and have broad application potential in the semiconductor market.

[0004] The synthesis of tris(dialkylamino)cyclopentadienyl metal precursors is often done with lithium dialkylamide LiNR 1 R 2 , metal halides, and cyclopentadiene monomer (RCpH) as raw materials. For example, Japanese Patent Application Laid-Open (JP2012201652A) discloses a method for producing an amino zirconium compound. Example 1 of this patent discloses mixing zirconium tetrachloride and dimethylamine, adding n-butyl lithium to the mixture for reaction, and then adding cyclopentadiene monomer to react to produce tris(dimethylamino)cyclopentadienyl hafnium. The yield is only approximately 7%. Another example is Chinese Patent Application CN107188908A, which discloses a method for preparing tris(dimethylamino)cyclopentadienyl zirconium. Specifically, lithium dimethylamine and zirconium tetrachloride react to produce tetra(dimethylamino)zirconium, to which cyclopentadiene monomer is added dropwise to produce tris(dimethylamino)cyclopentadienyl zirconium. This process is a one-pot synthesis, simplifying the steps, but the process yield is only 31-35%.

[0005] Although the above process is a relatively mature synthetic route, the raw materials used in the process, dialkylamine, are gaseous or liquid, lithium dialkylamide is solid, some metal halides are solid, and cyclopentadiene monomer is liquid. Consequently, the reaction system contains a variety of raw materials in different states. In actual scale-up production operations, this multiphase reaction not only leads to incomplete material reaction and low process yield, but also results in poor process reproducibility, making it impossible to consistently obtain the desired product. Summary of the Invention

[0006] In order to solve the above defects of the prior art, the purpose of the present invention is to provide a heterogeneous synthesis method of cyclopentadienyl metal precursors, which can solve the problems of low yield and unstable process in traditional multiphase synthesis routes.

[0007] First, the present invention provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, comprising the following steps: mixing lithium dialkylamide, metal halide and a heterogeneous reaction catalyst for reaction, and then adding cyclopentadiene monomer for reaction.

[0008] Furthermore, the structure of the cyclopentadienyl metal precursor is represented by R z CpM(NR x R y )3, wherein M is selected from Ti, Zr, Hf, Cp is a cyclopentadienyl group, R, R x and R y independently selected from C1-C5 alkyl groups, and z is an integer from 0 to 5.

[0009] Furthermore, R x and R y Independently selected from methyl or ethyl.

[0010] Further, exemplary hafnium cyclopentadienyl precursors include: CpHf(NMe2)3, CpHf(NMeEt)3, CpHf(NEt2)3, (MeCp)Hf(NMe2)3, (MeCp)Hf(NMeEt)3, (MeCp)Hf(NEt2)3, (Me2Cp)Hf(NMe2)3, (Me2Cp)Hf(NMeEt)3, (Me2Cp)Hf(NEt2)3, (Me5Cp)Hf(NMe2)3, (Me5Cp)Hf(NMeEt)3, (Me5Cp)Hf(NEt2)3, etc.

[0011] Further, exemplary cyclopentadienyl zirconium precursors include: CpZr(NMe2)3, CpZr(NMeEt)3, CpZr(NEt2)3, (MeCp)Zr(NMe2)3, (MeCp)Zr(NMeEt)3, (MeCp)Zr(NEt2)3, (Me2Cp)Zr(NMe2)3, (Me2Cp)Zr(NMeEt)3, (Me2Cp)Zr(NEt2)3, (Me5Cp)Zr(NMe2)3, (Me5Cp)Zr(NMeEt)3, (Me5Cp)Zr(NEt2)3, etc.

[0012] Further, exemplary cyclopentadienyl titanium precursors include: CpTi(NMe2)3, CpTi(NMeEt)3, CpTi(NEt2)3, (MeCp)Ti(NMe2)3, (MeCp)Ti(NMeEt)3, (MeCp)Ti(NEt2)3, (Me2Cp)Ti(NMe2)3, (Me2Cp)Ti(NMeEt)3, (Me2Cp)Ti(NEt2)3, (Me5Cp)Ti(NMe2)3, (Me5Cp)Ti(NMeEt)3, (Me5Cp)Ti(NEt2)3, etc.

[0013] Furthermore, the structure of lithium dialkylamide is represented as LiN(R x R y )2,R x and R y As defined above.

[0014] Furthermore, the structure of the metal halide is expressed as MY4, where M is selected from Ti, Zr, and Hf, and Y represents a halogen. The metal halide includes at least one of fluoride, chloride, bromide, and iodide, preferably chloride or bromide.

[0015] Furthermore, the molar equivalent ratio of the metal halide to the lithium dialkylamide is 1:4-6.

[0016] Furthermore, the heterogeneous reaction catalyst has the following structure:

[0017] ;

[0018] Wherein, R1 is a C2-C6 alkenyl or C2-C6 alkynyl, R2 is a substituted or unsubstituted phenyl, R3 is any one of H, a C1-C5 straight chain or branched alkyl, X is Cl or Br, and n is 0 or 1.

[0019] Furthermore, R1 is any one of vinyl, propenyl, allyl, butenyl, and ethynyl, preferably vinyl.

[0020] Furthermore, R2 is any one of phenyl, benzyl, phenethyl, and phenyl substituted with 1-5 methyl groups.

[0021] Furthermore, the R3 includes but is not limited to any one of H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, and tert-butyl.

[0022] In one embodiment, R1 is vinyl, R3 is H, and n is 0.

[0023] In one embodiment, R1 is vinyl, R2 is phenyl, R3 is H, X is Cl, and n is 1.

[0024] In one embodiment, R1 is vinyl, R2 is benzyl, R3 is H, X is Cl, and n is 1.

[0025] In one embodiment, R1 is vinyl, R2 is dimethyl-substituted phenyl, R3 is H, X is Br, and n is 1.

[0026] In one embodiment, R1 is vinyl, R2 is a phenyl group substituted with a methyl group, R3 is a methyl group, X is Br, and n is 1.

[0027] Furthermore, the heterogeneous reaction catalyst is used in an amount of 0.1%-10% of the molar equivalent of the metal halide, such as, but not limited to, 0.1%, 0.5%, 1.0%, 2.0%, 3.0%, 4.0%, 5.0%, 6.0%, 7.0%, 8.0%, 9.0%, 10.0%, etc.

[0028] Furthermore, the structure of the cyclopentadiene monomer is represented by R z Cp, R and z have the same meanings as defined above.

[0029] Furthermore, the molar equivalent ratio of the metal halide to the cyclopentadiene monomer is 1:1-2.

[0030] Furthermore, a solvent is added to the heterogeneous synthesis method, and the solvent is selected from at least one of an alkane organic solvent and an aromatic hydrocarbon organic solvent; the alkane organic solvent includes but is not limited to at least one of n-pentane, n-hexane, and n-octane, and the aromatic hydrocarbon organic solvent includes but is not limited to at least one of benzene, toluene, and ethylbenzene; the mass volume ratio of the metal halide to the solvent is 0.05-0.2:1 kg / L.

[0031] Furthermore, the dialkylamide lithium can be commercially available or prepared by reacting dialkylamine and alkyllithium.

[0032] In some embodiments, the heterogeneous synthesis method of the cyclopentadienyl metal precursor comprises the following steps:

[0033] S1, adding solvent, dialkylamine and alkyllithium into a reaction kettle for mixed reaction;

[0034] S2, adding a heterogeneous reaction catalyst and a metal halide to carry out a reaction;

[0035] S3, adding cyclopentadiene monomer to react;

[0036] S4. Filter and distill the cyclopentadienyl metal precursor product.

[0037] Furthermore, the structure of the dialkylamine is represented by HNR x R y , R x and R y The dialkylamine has the same definition as above. The dialkylamine can be introduced into the reaction in liquid or solution form or in gaseous form.

[0038] Furthermore, the molar equivalent ratio of the dialkylamine to the metal halide is 4-6:1.

[0039] Furthermore, the alkyl lithium is selected from at least one of methyl lithium, n-butyl lithium, tert-butyl lithium, and phenyl lithium.

[0040] Furthermore, the molar equivalent ratio of the alkyl lithium to the metal halide is 4-6:1.

[0041] Furthermore, the feeding temperature in S1 is controlled to be lower than -15°C, the temperature of the mixed reaction in S1 is -30~30°C, and the reaction time is 1-24h.

[0042] Furthermore, the reaction temperature in S2 is 30-50°C, preferably 40-45°C; and the reaction time is 4-24h.

[0043] Furthermore, in S3, the reaction temperature is adjusted to 20-28° C. and cyclopentadiene monomer is added. After the addition is completed, the reaction temperature is adjusted to 30-50° C., preferably 40-45° C. for reaction, and the reaction time is 8-24 hours.

[0044] Beneficial effects of the present invention:

[0045] (1) This application uses a suitable heterogeneous reaction catalyst to solve many defects of the traditional multiphase synthesis process of cyclopentadienyl metal precursors, and obtains a higher reaction yield and a more stable synthesis effect in the kilogram-level reaction scale-up process, effectively improving the process efficiency and saving the process cost.

[0046] (2) This application controls the relative amounts of raw materials, such as equivalent ratio, order of material addition, reaction temperature and reaction time, which can further improve the reaction yield and product quality, and enhance process reliability and safety.

[0047] (3) The heterogeneous synthesis method of the present application has high industrial application value and can be used in the industrial production of cyclopentadienyl titanium / zirconium / hafnium precursors. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 : The heterogeneous reaction catalyst of Example 1 1 H NMR characterization diagram.

[0049] Figure 2 : Example 1 obtained product CpHf (NMe2) 3 1 H NMR characterization diagram.

[0050] Figure 3 : The heterogeneous reaction catalyst of Example 2 1 H NMR characterization diagram.

[0051] Figure 4 : The heterogeneous reaction catalyst of Example 3 1 H NMR characterization diagram.

[0052] Figure 5 : Example 4 obtained product CpZr (NMe2) 3 1 H NMR characterization chart. DETAILED DESCRIPTION

[0053] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0054] Example 1

[0055] This embodiment provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpHf(NMe2)3, comprising the following steps:

[0056] S1. Add 18 L of n-hexane to a 50 L reactor. After cooling the reactor to -18°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyl lithium solution dropwise. Maintain the reaction temperature at around -15°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0057] S2. Add 0.011 kg (0.39 mol, 0.05 eq) of a heterogeneous reaction catalyst, followed by 2.5 kg (7.81 mol, 1.0 eq) of hafnium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition. After the addition is complete, react at 45°C for 4 hours. The heterogeneous reaction catalyst (CAS: 118-10-5) has the following structure:

[0058] The HNMR characterization spectrum of the heterogeneous reaction catalyst is shown in the attached Figure 1 , the characterization data is 1 HNMR (400 MHz, CDCl3): δ 8.88 (d, J = 4.5 Hz, 1H), 8.12 (d, J = 8.4 Hz, 1H), 7.98(d, J = 8.5 Hz, 1H), 7.72 – 7.64 (m, 1H), 7.60 (d, J = 4.5 Hz, 1H), 7.48 (dd, J =11.2, 4.1 Hz, 1H), 5.99 (ddd, J = 16.4, 11.1, 7.6 Hz, 1H), 5.69 (t, J = 5.6 Hz,1H), 5.04 (s, 1H), 5.01 (d, J = 6.7 Hz, 1H), 3.29 – 3.20 (m, 1H), 3.09 (td, J =9.3, 4.6 Hz, 1H), 2.96 – 2.83 (m, 2H), 2.75 (dt, J = 13.1, 8.8 Hz, 1H), 2.22(dd, J = 16.6, 8.1 Hz, 1H), 1.99 (dd, J = 12.1, 10.3 Hz, 1H), 1.50 (dd, J = 19.0,10.7 Hz, 2H), 1.35 – 1.13 (m, 2H), 0.87 (dd, J = 14.6, 6.9 Hz, 1H).

[0059] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The filtrate was filtered, and the solvent was removed by distillation. 2.49 kg of the product was then recovered by vacuum distillation, yielding a calculated yield of 85.0%.

[0060] The product structure was characterized by HNMR (see Appendix Figure 2 ), the characterization data is: 1 HNMR(C6D6): δ2.96 (S,18H,N(CH3)2), 6.03(S,5H,C5H5).

[0061] Example 2

[0062] This embodiment provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpHf(NMe2)3, comprising the following steps:

[0063] S1. Add 18 L of n-hexane to a 50 L reactor. After cooling the reactor to -15°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyl lithium solution dropwise. Maintain the reaction temperature at around -10°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0064] S2. Add 0.011 kg (0.39 mol, 0.05 eq) of a heterogeneous reaction catalyst, followed by 2.5 kg (7.81 mol, 1.0 eq) of hafnium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition process. After the addition is complete, react at 45°C for 4 hours. The heterogeneous reaction catalyst (CAS: 485-71-2) has the following structure:

[0065] The HNMR characterization spectrum of the heterogeneous reaction catalyst is shown in the attached Figure 3 The characterization data is 1 HNMR (400 MHz, CDCl3): δ 8.86 (d, J = 4.5 Hz, 1H), 8.12 (d, J = 8.5 Hz, 1H), 8.03(d, J = 8.4 Hz, 1H), 7.69 (t, J = 7.6 Hz,1H), 7.58 (d, J = 4.4 Hz, 1H), 7.50 (t, J=7.6 Hz, 1H), 5.75 (ddd, J = 17.7, 10.2, 7.7 Hz, 1H), 5.65 (d, J = 4.1 Hz, 1H), 4.98 (s, 0.5H), 4.94 (d, J = 2.2 Hz, 1H), 4.90 (s, 0.5H), 3.47 – 3.36 (m, 1H), 3.19 – 3.02 (m, 2H), 2.72 – 2.58 (m, 2H), 2.27 (s, 1H), 1.83 (d, J = 14.9 Hz,1H), 1.62 – 1.42 (m, 2H), 1.30 – 1.15 (m, 2H), 0.92 – 0.77 (m, 1H).

[0066] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The filtrate was filtered, and the solvent was removed by distillation. 2.44 kg of the product was then recovered by vacuum distillation, yielding a calculated yield of 83.20%.

[0067] Example 3

[0068] This embodiment provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpHf(NMe2)3, comprising the following steps:

[0069] S1. Add 18 L of n-hexane to a 50 L reactor. After the temperature in the reactor is cooled to -15°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyllithium solution dropwise. Maintain the reaction temperature at around -15°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0070] S2. Add 0.016 kg (0.39 mol, 0.05 eq) of a heterogeneous reaction catalyst, followed by 2.5 kg (7.81 mol, 1.0 eq) of hafnium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition process. After the addition is complete, react at 45°C for 4 hours. The heterogeneous reaction catalyst (CAS: 69257-04-1) has the following structure:

[0071] The HNMR characterization spectrum of the heterogeneous reaction catalyst is shown in the attached Figure 4 , the characterization data is 1H NMR (400 MHz, CDCl3): δ 8.81 (d, J = 4.4 Hz, 1H), 8.11 (d, J = 7.8 Hz,1H), 7.82 (d, J = 4.4 Hz, 1H), 7.73 (d, J = 7.7 Hz, 1H), 7.66 (d, J = 7.3 Hz, 2H),7.46 (d, J = 6.1 Hz, 1H), 7.26 – 7.23 (m, 2H), 7.19 (t, J = 7.4 Hz, 2H), 6.54 (d, J = 4.3 Hz, 1H), 5.71 (q, J = 12.0 Hz, 2H), 5.42 (ddd, J = 16.9, 10.4, 6.3 Hz,1H), 5.24 (s, 1H), 5.19 (s, 0.5H), 4.94 (d, J = 10.4 Hz, 1H), 4.74 (s, 1H), 4.01 (t, J = 9.0 Hz, 1H), 3.64 (d, J = 12.7 Hz, 1H), 3.13 (dt, J = 12.1, 9.6 Hz,2H), 2.48 (s, 1H), 2.13 (t, J = 11.7 Hz, 1H), 1.99 – 1.89 (m, 2H), 1.61 (s, 1H), 1.08 (s, 1H), 0.87 (d, J = 6.8 Hz, 0.5H).

[0072] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The filtrate was filtered, and the solvent was removed by distillation. 2.68 kg of the product was then recovered by vacuum distillation, yielding a calculated yield of 91.20%.

[0073] Example 4

[0074] This embodiment provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpZr(NMe2)3, comprising the following steps:

[0075] S1. Add 18 L of n-hexane to a 50 L reactor. After cooling the reactor to -20°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyl lithium solution dropwise. Maintain the reaction temperature at around -5°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0076] S2. Add 0.016 kg (0.39 mol, 0.05 eq) of a heterogeneous reaction catalyst, followed by 1.82 kg (7.81 mol, 1.0 eq) of zirconium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition process. After the addition is complete, react at 45°C for 4 hours. The heterogeneous reaction catalyst (CAS: 69257-04-1) has the following structure:

[0077] .

[0078] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The filtrate was filtered, and the solvent was removed by distillation. 2.02 kg of the product was then recovered by vacuum distillation, yielding a calculated yield of 89.70%.

[0079] The product structure was characterized by HNMR (see Appendix Figure 5 ), the characterization data is 1 H NMR(C6D6): δ2.92(S,18H,N(CH3)2), 6.06(S,5H,C5H5).

[0080] Comparative Example 1

[0081] This comparative example provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpHf(NMe2)3, comprising the following steps:

[0082] S1. Add 18 L of n-hexane to a 50 L reactor. After cooling the reactor to -18°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyl lithium solution dropwise. Maintain the reaction temperature at around -15°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0083] S2. Add 2.5 kg (7.81 mol, 1.0 eq) of hafnium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition process. After the addition is completed, react at 45°C for 4 hours.

[0084] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The mixture was filtered, and the filtrate was distilled to remove the solvent. 1.54 kg of the product was then distilled under reduced pressure, yielding 52.5%.

[0085] Comparative Example 2

[0086] This comparative example provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpHf(NMe2)3, comprising the following steps:

[0087] S1. Add 18 L of n-hexane to a 50 L reactor. After the temperature in the reactor is cooled to -15°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyllithium solution dropwise. Maintain the reaction temperature at around -15°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0088] S2. Add 3.29 kg (7.81 mol, 1.0 eq) of a heterogeneous reaction catalyst, followed by 2.5 kg (7.81 mol, 1.0 eq) of hafnium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition. After the addition is complete, react at 45°C for 4 hours. The heterogeneous reaction catalyst (CAS: 69257-04-1) has the following structure:

[0089] .

[0090] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The filtrate was filtered, and the solvent was removed by distillation. 1.83 kg of the product was then recovered by vacuum distillation, yielding a calculated yield of 62.3%.

[0091] Comparative Example 3

[0092] This comparative example provides a heterogeneous synthesis method of a cyclopentadienyl metal precursor, CpHf(NMe2)3, comprising the following steps:

[0093] S1. Add 18 L of n-hexane to a 50 L reactor. After cooling the reactor to -18°C, introduce 1.58 kg (35.15 mol, 4.5 eq) of dimethylamine. After the addition of dimethylamine is complete, slowly add 9.00 kg (32.80 mol, 4.2 eq) of n-butyl lithium solution dropwise. Maintain the reaction temperature at around -15°C during the addition. After the addition is complete, naturally raise the temperature to room temperature (25±3°C) and react for 1 hour.

[0094] S2. Add 0.072 kg (0.39 mol, 0.05 eq) of a heterogeneous reaction catalyst and 2.5 kg (7.81 mol, 1.0 eq) of hafnium tetrachloride. Maintain the reaction temperature between 40°C and 45°C during the addition. After the addition is complete, react at 45°C for 4 h. The heterogeneous reaction catalyst is trimethylbenzyl ammonium chloride (CAS: 56-93-9).

[0095] S3. After cooling the reactor to 25°C, 0.72 kg (10.93 mol, 1.4 eq) of cyclopentadiene monomer was added dropwise. After completion of addition, the reaction was incubated at 45°C for 12 h. The mixture was filtered, and the filtrate was distilled to remove the solvent. 1.79 kg of the product was then distilled under reduced pressure for a yield of 61.0%.

[0096] Performance testing method:

[0097] 1. Yield: The calculation formula is (actual product mass / theoretical product mass)*100%.

[0098] 2. Process Stability: Five batches of product were synthesized using the synthesis method of each example. The number of unsatisfactory yields was calculated (yields ≥ 85% were considered acceptable, and those below 85% were considered unsatisfactory). A greater number of unsatisfactory yields indicated poorer process stability. If the yield of all five batches was ≥ 85%, the process stability was considered good. The statistical results are shown in Table 1.

[0099] Table 1

[0100] Serial number Example 1 Example 2 Example 3 Example 4 Comparative Example 1 First batch yield 86.2% 89.0% 90.4% 87.5% 67.5% Second batch yield 85.8% 87.9% 88.0% 84.3% 45.0% The third batch yield 89.5% 85.1% 86.5% 85.0% 50.7% The fourth batch yield 85.0% 83.2% 91.2% 89.7% 52.5% The fifth batch yield 84.3% 84.8% 89.9% 90.3% 62.2%

[0101] Analysis: As shown in Table 1, the synthesis method with the addition of a heterogeneous reaction catalyst in Examples 1-4 has a higher yield and process stability, while the multiphase synthesis process without the use of a heterogeneous reaction catalyst has not only a low yield but also poor process stability.

[0102] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0103] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A heterogeneous synthesis method of a cyclopentadienyl metal precursor, characterized in that: The following steps are involved: After lithium dialkylamide, metal halide, and a heterogeneous reaction catalyst are mixed for reaction, cyclopentadiene monomer is added for reaction; the heterogeneous reaction catalyst has the following structure: Wherein, R1 is vinyl, R2 is benzyl or phenethyl, R3 is H, X is Cl or Br, and n is 0 or 1; The structure of metal halide is represented by MY4, where M is selected from Ti, Zr, Hf, and Y represents halogen; The amount of heterogeneous reaction catalyst used is 0.1%-10% of the molar equivalent of the metal halide; The structure of the cyclopentadienyl metal precursor is represented by R z CpM(NR x R y )3, wherein M is selected from Ti, Zr, Hf, Cp is a cyclopentadienyl group, R, R x and R y independently selected from C1-C5 alkyl groups, and z is an integer from 0 to 5.

2. The heterogeneous synthesis method according to claim 1, wherein R1 is vinyl, R3 is H, and n is 0.

3. The heterogeneous synthesis method according to claim 1, wherein R1 is vinyl, R2 is benzyl, R3 is H, X is Cl, and n is 1.

4. The heterogeneous synthesis method according to claim 1, wherein The molar equivalent ratio of the metal halide to the lithium dialkylamide is 1:4-6, and the molar equivalent ratio of the metal halide to the cyclopentadiene monomer is 1:1-2.

5. The heterogeneous synthesis method according to claim 1, wherein The heterogeneous synthesis method of the cyclopentadienyl metal precursor comprises the following steps: S1, adding solvent, dialkylamine and alkyllithium into a reaction kettle for mixed reaction; S2, adding a heterogeneous reaction catalyst and a metal halide to carry out a reaction; S3, adding cyclopentadiene monomer to react; S4. Filter and distill the cyclopentadienyl metal precursor product.

6. The heterogeneous synthesis method according to claim 5, wherein The molar equivalent ratio of the dialkylamine to the metal halide is 4-6:1; and / or the alkyl lithium is selected from at least one of methyl lithium, n-butyl lithium, and tert-butyl lithium; and / or the molar equivalent ratio of the alkyl lithium to the metal halide is 4-6:

1.

7. The heterogeneous synthesis method according to claim 5 or 6, wherein The temperature of the mixed reaction in S1 is -30°C to 30°C, and the reaction time is 1-24h; and / or, the reaction temperature in S2 is 30-50° C. and the reaction time is 4-24 h; And / or, in S3, the reaction temperature is adjusted to 20-28° C. and cyclopentadiene monomer is added. After the addition is completed, the reaction temperature is adjusted to 30-50° C. for reaction for 8-24 hours.

Images