Synthetic method of ruthenium complex precursor

Abstract

The invention discloses a ruthenium complex precursor synthesis method, which comprises: adding a ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 L of ethanol into a 5000 ml multi-port reaction bottle under a nitrogen atmosphere, and stirring to dissolve; dropwise adding pyridine (163.3 g, 2.06 mol) into a reaction system at room temperature, after dropwise adding is completed, heating to reflux and reacting for 3 hours until the system becomes red, slowly recovering to room temperature, and filtering; the preparation method comprises the following steps: adding a sodium acetate solution into a reaction kettle, stirring, filtering, concentrating filtrate to 2 / 3 of the volume, cooling to 0 DEG C, dropwise adding a tetrahydrofuran solution of sodium acetylcyclopentadienyl (820 mL, 0.82 mol) with the molar concentration of 1 mol / L, slowly recovering to room temperature after dropwise adding, continuously reacting for 10 hours, draining the solvent, extracting by using dichloromethane, filtering, draining the filtrate, pulping a crude product by using ethanol, filtering, washing by using ethanol, and drying to obtain a finished product. 91.8 g of the diacetyl ruthenium dicyclopentadienyl intermediate is obtained, and the yield is 71%; and borane dimethyl sulfide reduction is carried out. The method has the advantages of simple and easily available reaction raw materials, convenient operation, mild reaction conditions, low cost and high safety coefficient.

Description

Technical Field

[0001] The invention relates to the technical field of chemical synthesis, and more specifically to a method for synthesizing a ruthenium complex precursor. Background Art

[0002] High dielectric materials, such as TiO2, Ta2O5, and (Ba,Sr)TiO3, have been attempted in recent years for the next generation of dynamic random access memory (DRAM). In order for this application to be successful, it is very important to select a suitable bottom electrode material. The electrode requirements should not react with oxygen (O) or silicon (Si), and should also prevent diffusion between the dielectric layer and the underlying polysilicon plug in any direction. In addition, compatible etching processes, good morphological stability, and reliable adhesion properties are necessary conditions for the application of such materials in electronic devices. Ruthenium is one of the promising electrode materials for high dielectric capacitors because it can prevent the diffusion of O during the fabrication and annealing of dielectric materials by forming a conductive oxide film RuO2. In addition, ruthenium has a relatively low resistivity, and dry etching of the film is easily accomplished using reactive ion etching.

[0003] To construct capacitor electrodes of Ru or RuO2 thin films, an atomic layer deposition (ALD) technology with good conformality is required. Compared with traditional physical vapor deposition or chemical vapor deposition techniques, the ALD process has many inherent advantages, including good conformality, accurate thickness controllability, large-area uniformity, and high film quality at low growth temperatures. Based on this, in recent years, bis(ethylcyclopentadienyl)ruthenium(II) has gradually come into the field of vision of researchers. Bis(ethylcyclopentadienyl)ruthenium(II) is a liquid at room temperature and can be dissolved in organic solvents such as hydrocarbons and carbon tetrachloride. It not only has good stability and high vapor pressure, but also exhibits a fairly high reactivity. It is a hot topic in the current ALD research field.

[0004] The currently reported methods for synthesizing bis(ethylcyclopentadienyl)ruthenium(II) are as follows: 1) using ruthenium trichloride hydrate and cracked ethylcyclopentadienyl monomer as raw materials, alcohol as solvent, and zinc powder (or magnesium powder) for reduction to obtain bis(ethylcyclopentadienyl)ruthenium with a yield of up to 87%; 2) first preparing a bis(ethylcyclopentadienyl)ruthenium intermediate, and then reacting it with butyl lithium and ethyl bromide to obtain bis(ethylcyclopentadienyl)ruthenium; 3) first preparing bis(ethylcyclopentadienyl)ruthenium, and then performing an acylation reaction to obtain diacetyl bis(ethylcyclopentadienyl)ruthenium, and finally using palladium carbon for hydrogenation reduction to obtain bis(ethylcyclopentadienyl)ruthenium.

[0005] Technical problems of existing technologies Route 1: The reaction requires high-purity ethylcyclopentadiene monomer, which requires that the purity of the cracked ethylcyclopentadiene dimer is very high, and the collection of impurity cyclopentadiene should be avoided during the cracking process; the cracking generally needs to be heated to above 180°C, which has high requirements for equipment; when zinc powder is used as a reducing agent, its equivalent is far in excess, and most of the zinc powder that does not participate in the reaction is wasted, which greatly increases the cost of this route.

[0006] Route 2: The reaction also requires the use of zinc powder to prepare bis(cyclopentadienyl)ruthenium; and the reaction uses the highly flammable raw material butyl lithium. Commercially available butyl lithium is generally diluted in an alkane solvent, which produces a large amount of waste liquid during use, increasing the cost of hazardous waste disposal.

[0007] Route 3: The reaction is carried out in three steps, and the intermediates in each step must be separated separately, resulting in a low final yield; the third step uses palladium carbon for hydrogenation reduction, which requires the use of special equipment such as an autoclave.

[0008] In general, the synthetic routes described above can be classified as unsatisfactory from the perspectives of economy, safety and industrialization. Summary of the invention

[0009] 1. Technical issues to be resolved In view of the problems existing in the prior art, the present invention provides a method for synthesizing a ruthenium complex precursor to solve the technical problems mentioned in the background technology.

[0010] (II) Technical solution To achieve the above object, the present invention provides the following technical solution: a method for synthesizing a ruthenium complex precursor, comprising the following steps: Step 1: Add ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 L of ethanol into a 5000 ml multi-necked reaction bottle under nitrogen atmosphere, and stir to dissolve; Step 2: Pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature. After the addition was complete, the mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature and filtered. Step 3: The filtrate was concentrated to 2 / 3 of the volume and then cooled to 0 °C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (820 mL, 0.82 mol) with a molar concentration of 1 mol was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol, filtered, and washed with ethanol to obtain 91.8 g of diacetyl bis(cyclopentadienyl) ruthenate intermediate with a yield of 71%.

[0011] The present invention is further configured as follows: in the step 1, diacetyl bis(cyclopentadienyl)ruthenate (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran are added to a 2000 ml multi-necked reaction bottle under a nitrogen atmosphere, the temperature is lowered to 0 ° C, and a 2 mol / L borane dimethyl sulfide solution (240 mL, 0.48 mol) is added dropwise.

[0012] The present invention is further configured that, in the above steps, after the dropwise addition is completed, the room temperature is slowly restored and the reaction is carried out for 12 hours, the temperature is lowered to 0°C, and 250 ml of methanol is added dropwise to quench the reaction. The solvent is drained, and the crude product is distilled under reduced pressure to obtain 51.7 g of yellow liquid, with a yield of 75%.

[0013] (III) Beneficial effects Compared with the prior art, the present invention provides a method for synthesizing a ruthenium complex precursor, which has the following beneficial effects: The technical problem to be solved by the present invention is to provide a method for preparing an ALD precursor ruthenium complex, the whole process operation conditions are convenient, and the target product is obtained by a two-step method; the reaction process is gentle, the energy consumption is low, and the safety is high; the raw material sources are wide and cheap, the product yield is high, and the process stability is good; it avoids the use of materials and equipment with high risk factors, which is conducive to industrial production and expansion. In addition, the reaction raw materials of this scheme are simple and easy to obtain, the operation is convenient, the reaction conditions are mild, the cost is low, the safety factor is high, the yield is high, and it is suitable for industrial scale-up production. DETAILED DESCRIPTION Example

[0014] Under nitrogen atmosphere, ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 liters of ethanol were added to a 5000 ml multi-mouth reaction bottle, stirred and dissolved, pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature, and the addition was completed. The mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature. The mixture was filtered, and the filtrate was concentrated to 2 / 3 of the volume and then cooled to 0 ° C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (820 mL, 0.82 mol) with a molar concentration of 1 mol per liter was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol, filtered, and washed with ethanol to obtain 91.8 g of diacetyl bis(cyclopentadienyl) ruthenium intermediate with a yield of 71%.

[0015] Under nitrogen atmosphere, add diacetyl ruthenocene (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran to a 2000 ml multi-mouth reaction bottle, cool to 0 °C, drop 2 mol / L borane dimethyl sulfide solution (240 mL, 0.48 mol), and after the addition is complete, slowly return to room temperature and react for 12 hours, cool to 0 °C, drop 250 ml of methanol to quench the reaction. Drain the solvent, and distill the crude product under reduced pressure to obtain 51.7 g of yellow liquid with a yield of 75%.

[0016] Embodiment 2: Different from embodiment 1, the equivalent of acetylcyclopentadienyl sodium is increased in this embodiment.

[0017] Under nitrogen atmosphere, ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 liters of ethanol were added to a 5000 ml multi-mouth reaction bottle, stirred and dissolved, pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature, and the addition was completed. The mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature. The mixture was filtered, and the filtrate was concentrated to 2 / 3 of the volume and then cooled to 0 ° C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (1025 mL, 1.025 mol) with a molar concentration of 1 mol per liter was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol, filtered, and washed with ethanol to obtain 107.3 g of diacetyl bis(cyclopentadienyl) ruthenium intermediate with a yield of 83%.

[0018] Under nitrogen atmosphere, add diacetyl ruthenocene (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran to a 2000 ml multi-mouth reaction bottle, cool to 0 °C, drop borane dimethyl sulfide solution (240 mL, 0.48 mol) with a molar concentration of 2 mol / L, and slowly return to room temperature after the addition is complete. After reacting for 12 hours, cool to 0 °C and drop 250 ml of methanol to quench the reaction. Drain the solvent and distill the crude product under reduced pressure to obtain 51.7 g of yellow liquid with a yield of 75%.

[0019] Example 3: Different from Example 2, this example increases the equivalent of borane dimethyl sulfide. Under nitrogen atmosphere, ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 liters of ethanol were added to a 5000 ml multi-mouth reaction bottle, stirred and dissolved, pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature, and the addition was completed. The mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature. The mixture was filtered, and the filtrate was concentrated to 2 / 3 of the volume and then cooled to 0 ° C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (1025 mL, 1.025 mol) with a molar concentration of 1 mol per liter was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol, filtered, and washed with ethanol to obtain 107.3 g of diacetyl bis(cyclopentadienyl) ruthenium intermediate with a yield of 83%.

[0020] Under nitrogen atmosphere, add diacetyl ruthenocene (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran to a 2000 ml multi-mouth reaction bottle, cool to 0 °C, and drop borane dimethyl sulfide solution (720 mL, 1.44 mol) with a molar concentration of 2 mol / L. After the addition is complete, slowly return to room temperature and react for 12 hours, cool to 0 °C, and drop 250 ml of methanol to quench the reaction. Drain the solvent, and distill the crude product under reduced pressure to obtain 58.6 g of yellow liquid with a yield of 85%.

[0021] Comparative Example 1: Unlike Example 1, this embodiment did not perform the filtrate concentration operation after adding pyridine. Under nitrogen atmosphere, ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 liters of ethanol were added to a 5000 ml multi-mouth reaction bottle, stirred and dissolved, pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature, and the addition was completed. The mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature. The mixture was filtered and the filtrate was cooled to 0 ° C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (820 mL, 0.82 mol) with a molar concentration of 1 mol / L was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol and filtered, and washed with ethanol to obtain 71.1 g of diacetyl bis(cyclopentadienyl) ruthenium intermediate with a yield of 55%.

[0022] Add diacetyl ruthenocene (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran to a 2000 ml multi-mouth reaction bottle in a nitrogen atmosphere, cool to 0 °C, and drop 2 mol / L borane dimethyl sulfide solution (240 mL, 0.48 mol). After the addition is complete, slowly return to room temperature and react for 12 hours, cool to 0 °C, and drop 250 ml of methanol to quench the reaction. Drain the solvent, and distill the crude product under reduced pressure to obtain 51.7 g of a yellow liquid with a yield of 75%.

[0023] Comparative Example 2: Different from Example 1, this example uses column chromatography to purify bis(ethylcyclopentadienyl)ruthenium. Ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 liters of ethanol were added to a 5000 ml multi-mouth reaction bottle under a nitrogen atmosphere, stirred and dissolved, pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature, and the addition was completed. The mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature. The mixture was filtered, and the filtrate was concentrated to 2 / 3 of the volume and then cooled to 0 ° C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (820 mL, 0.82 mol) with a molar concentration of 1 mol per liter was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol, filtered, and washed with ethanol to obtain 91.8 g of diacetyl bis(cyclopentadienyl) ruthenium intermediate with a yield of 71%.

[0024] Add diacetyl ruthenocene (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran to a 2000 ml multi-mouth reaction bottle in a nitrogen atmosphere, cool to 0 °C, and drop 2 mol / L borane dimethyl sulfide solution (240 mL, 0.48 mol). After the addition is complete, slowly return to room temperature and react for 12 hours, cool to 0 °C, and drop 250 ml of methanol to quench the reaction. Drain the solvent, separate and purify using column chromatography, with petroleum ether as the eluent, to obtain 48.3 g of yellow liquid with a yield of 70%.

[0025] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0026] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be listed as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for synthesizing a ruthenium complex precursor, characterized in that: The following steps are involved: Step 1: Add ruthenium trichloride hydrate (112.8 g, 0.41 mol) with a ruthenium content of 37% and 1.6 L of ethanol into a 5000 ml multi-necked reaction bottle under nitrogen atmosphere, and stir to dissolve; Step 2: Pyridine (163.3 g, 2.06 mol) was added dropwise to the reaction system at room temperature. After the addition was complete, the mixture was heated to reflux and reacted for 3 hours. The system turned red and slowly returned to room temperature and filtered. Step 3: The filtrate was concentrated to 2 / 3 of the volume and then cooled to 0 °C. A tetrahydrofuran solution of acetylcyclopentadienyl sodium (820 mL, 0.82 mol) with a molar concentration of 1 mol was added dropwise. After the addition was completed, the mixture was slowly returned to room temperature and the reaction was continued for 10 hours. The solvent was drained, extracted with dichloromethane, filtered, the filtrate was drained, the crude product was slurried with ethanol, filtered, and washed with ethanol to obtain 91.8 g of diacetyl bis(cyclopentadienyl) ruthenate intermediate with a yield of 71%.

2. The method for synthesizing a ruthenium complex precursor according to claim 1, characterized in that: In the step 1, diacetyl ruthenocene (75.7 g, 0.24 mol) and 200 ml of tetrahydrofuran were added to a 2000 ml multi-necked reaction bottle under nitrogen atmosphere, the temperature was lowered to 0° C., and a 2 mol borane dimethyl sulfide solution (240 mL, 0.48 mol) was added dropwise.

3. The method for synthesizing a ruthenium complex precursor according to claim 2, characterized in that: In the above steps, after the addition was completed, the room temperature was slowly restored and the reaction was continued for 12 hours, then the temperature was lowered to 0°C and 250 ml of methanol was added to quench the reaction. The solvent was drained and the crude product was distilled under reduced pressure to obtain 51.7 g of yellow liquid with a yield of 75%.