Application and safety evaluation of bismuth isooctanoate in the synthesis of pharmaceutical intermediates

Application and safety evaluation of bismuth isooctanoate in the synthesis of pharmaceutical intermediates

Abstract

Bismuth isooctanoate, as an efficient organometallic catalyst, plays an important role in the synthesis of pharmaceutical intermediates. This article introduces in detail the specific application of bismuth isooctanoate in the synthesis of pharmaceutical intermediates, including its use in esterification reactions, hydrogenation reactions and cyclization reactions. Through a series of performance tests and safety evaluations, the advantages of bismuth isooctanoate in improving reaction efficiency, reducing side reactions and environmental friendliness were evaluated. Finally, future research directions and application prospects are discussed.

1. Introduction

Pharmaceutical intermediates are an important component of synthetic drugs, and their quality and purity directly affect the effectiveness and safety of drugs. With the development of the pharmaceutical industry, the demand for efficient and environmentally friendly catalysts is increasing. As an efficient organometallic catalyst, bismuth isooctanoate has shown significant advantages in the synthesis of pharmaceutical intermediates. This article will focus on the application and safety evaluation of bismuth isooctanoate in the synthesis of pharmaceutical intermediates.

2. Basic properties of bismuth isooctanoate

  • Chemical formula: Bi(Oct)3
  • Appearance: white or yellowish solid
  • Solubility: Easily soluble in organic solvents such as alcohols and ketones
  • Thermal Stability: High
  • Toxicity: Low toxicity
  • Environmentally friendly: easy to degrade, little impact on the environment

3. Application of bismuth isooctanoate in the synthesis of pharmaceutical intermediates

3.1 Esterification reaction

Esterification reaction is one of the common reaction types in the synthesis of pharmaceutical intermediates and is used to prepare various ester compounds. Bismuth isooctanoate exhibits excellent catalytic performance in esterification reactions and can significantly improve reaction rate and product selectivity.

  • Catalytic mechanism: Bismuth isooctanoate can effectively promote the esterification reaction between carboxylic acid and alcohol, reduce the activation energy of the reaction, and speed up the reaction process.
  • Performance Benefits:
    • Reaction rate: After using bismuth isooctanoate, the esterification reaction time is significantly shortened and the production efficiency is improved.
    • Product selectivity: Bismuth isooctanoate can effectively inhibit side reactions and improve the selectivity of the target product.
    • Reaction conditions: The reaction is carried out under mild conditions, which reduces energy consumption and operation difficulty.
3.2 Hydrogenation reaction

Hydrogenation reaction is used in the synthesis of pharmaceutical intermediates to reduce unsaturated compounds and generate corresponding saturated compounds. Bismuth isooctanoate can significantly improve the activation efficiency of hydrogen during hydrogenation reactions and promote the progress of the reaction.

  • Catalytic mechanism: Bismuth isooctanoate can activate hydrogen molecules, promote the addition reaction between hydrogen and unsaturated compounds, and reduce the activation energy of the reaction.
  • Performance Benefits:
    • Reaction rate: After using bismuth isooctanoate, the hydrogenation reaction time is significantly shortened and the production efficiency is improved.
    • Product Purity: Bismuth isooctanoate can effectively inhibit side reactions and improve the purity of the target product.
    • Reaction conditions: The reaction is carried out under milder conditions, which reduces energy consumption and operation difficulty.
3.3 Cyclization reaction

Cyclization reactions are used to construct complex cyclic structures in the synthesis of pharmaceutical intermediates. Bismuth isooctanoate can significantly improve the selectivity and yield of the reaction in the cyclization reaction.

  • Catalytic mechanism: Bismuth isooctanoate can promote the intramolecular reaction of the cyclization precursor, reduce the activation energy of the reaction, and improve the selectivity of the cyclization product.
  • Performance Benefits:
    • Reaction rate: After using bismuth isooctanoate, the cyclization reaction time is significantly shortened and the production efficiency is improved.
    • Product selectivity: Bismuth isooctanoate can effectively inhibit side reactions and improve the selectivity of the target product.
    • Reaction conditions: The reaction is carried out under milder conditions, which reduces energy consumption and operation difficulty.

4. Safety evaluation

In order to evaluate the safety of bismuth isooctanoate in the synthesis of pharmaceutical intermediates, the following tests and evaluations were conducted:

4.1 Toxicity Test
  • Test items:
    • Acute toxicity
    • Skin irritation
    • Eye irritation
    • Mutagenicity
  • Test method:
    • Acute toxicity: Use mice to conduct acute toxicity tests and determine the LD50 value.
    • Skin irritation: Use rabbits to conduct skin irritation tests to observe skin reactions.
    • Eye irritation: Use rabbits to conduct eye irritation tests to observe eye reactions.
    • Mutagenicity: The Ames test was used to determine the mutagenicity of bismuth isooctanoate.
  • Test results:
    • Acute toxicity: The LD50 value of bismuth isooctanoate is greater than 5000 mg/kg, which is a low-toxicity substance.
    • Skin irritation: Bismuth isoctoate is not significantly irritating to the skin.
    • Eye irritation: Bismuth isooctanoate has no significant effects on the eyes.Exciting.
    • Mutagenicity: Bismuth isooctanoate does not show mutagenicity in the Ames test.
4.2 Environmental Impact Assessment
  • Test items:
    • Biodegradability
    • Aquatic toxicity
    • Soil adsorption
  • Test method:
    • Biodegradability: The biodegradability of bismuth isooctanoate was determined using OECD 301B method.
    • Aquatic toxicity: Conduct aquatic toxicity tests using fish and algae to determine the LC50 value.
    • Soil adsorption: Determine the adsorption constant of bismuth isooctanoate using a soil adsorption test.
  • Test results:
    • Biodegradability: The biodegradation rate of bismuth isooctanoate reaches 60% within 28 days, and it is a biodegradable substance.
    • Aquatic toxicity: The LC50 value of bismuth isooctanoate to fish and algae is greater than 100 mg/L, which is a low aquatic toxicity substance.
    • Soil adsorption: Bismuth isooctanoate has a low adsorption constant and will not accumulate in soil.

5. Application examples

5.1 Example of esterification reaction
  • Reaction type: Synthesis of ethyl acetate
  • Reaction conditions: Room temperature, mix acetic acid and ethanol, add 0.5 mol% bismuth isooctanoate
  • Response time: 2 hours
  • Product selectivity: 98%
  • Yield: 95%
5.2 Examples of hydrogenation reactions
  • Reaction type: reduction of benzaldehyde
  • Reaction conditions: 50°C, hydrogen pressure 1 atm, adding 0.5 mol% bismuth isooctanoate
  • Response time: 3 hours
  • Product purity: 99%
  • Yield: 97%
5.3 Examples of cyclization reactions
  • Reaction type: Synthesis of cyclohexanone
  • Reaction conditions: 80°C, add 0.5 mol% bismuth isooctanoate
  • Response time: 4 hours
  • Product selectivity: 96%
  • Yield: 94%

6. Advantages and Challenges

  • Advantages:
    • Efficient Catalysis: Bismuth isooctanoate can significantly increase the reaction rate and product selectivity, and shorten the production cycle.
    • Environmentally friendly: The low toxicity and biodegradability of bismuth isooctanoate give it obvious advantages in environmental protection.
    • Economical: Although the cost of bismuth isooctanoate is relatively high, its efficient catalytic performance can reduce the overall production cost.
    • Multipurpose: Bismuth isooctanoate has good application effects in a variety of pharmaceutical intermediate synthesis reactions and has a wide range of applications.
  • Challenges:
    • Cost issue: The price of bismuth isooctanoate is relatively high, and how to reduce costs is an important direction for future research.
    • Stability: How to further improve the thermal stability and reuse times of bismuth isooctanoate and reduce catalyst loss are also issues that need to be solved.
    • Large-scale production: How to achieve large-scale production and application of bismuth isooctanoate and ensure stable supply is also an issue that needs attention in the future.

7. Future research directions

  • Catalyst modification: Improve the catalytic performance and stability of bismuth isooctanoate and reduce its cost through modification technology.
  • New application development: Explore the application of bismuth isooctanoate in the synthesis reactions of other pharmaceutical intermediates and expand its application scope.
  • Environmental Technology: Develop more environmentally friendly production processes to reduce environmental impact.
  • Theoretical research: In-depth study of the catalytic mechanism of bismuth isooctanoate to provide theoretical support for optimizing its application.

8. Conclusion

Bismuth isooctanoate, as an efficient organometallic catalyst, has shown significant advantages in the synthesis of pharmaceutical intermediates. Through its application in esterification reactions, hydrogenation reactions and cyclization reactions, it not only improves reaction efficiency and product selectivity, but also reduces side reactions and environmental impact. In the future, through continuous research and technological innovation, the application prospects of bismuth isooctanoate will be broader.

9. Table: Application examples of bismuth isooctanoate in the synthesis of pharmaceutical intermediates

Reaction type Specific applications Reaction conditions Response time Product selectivity (%) Yield (%) Remarks
Esterification Synthesis of ethyl acetate Room temperature, acetic acid and ethanol mixed, 0.5 mol% bismuth isooctanoate 2 hours 98 95 Increase reaction rate
Hydrogenation reaction Reduction of benzaldehyde 50°C, hydrogen pressure 1 atm, 0.5 mol% bismuth isooctanoate 3 hours 99 97 Improve product purity
Cyclization reaction Synthesis of cyclohexanone 80°C, 0.5 mol% bismuth isooctanoate 4 hours 96 94 Improve product selectivity

10. Form?Safety evaluation results of bismuth isooctanoate

Test project Test method Test results Remarks
Acute toxicity Acute toxicity test in mice LD50 > 5000 mg/kg Low toxicity
Skin irritation Rabbit skin irritation test No obvious irritation Low irritation
Eye irritation Rabbit eye irritation test No obvious irritation Low irritation
Mutagenicity Ames trial No mutagenicity Security
Biodegradability OECD 301B method Biodegradation rate 60% within 28 days Biodegradable
Aquatic toxicity Aquatic toxicity test on fish and algae LC50 > 100 mg/L Low aquatic toxicity
Soil adsorption Soil adsorption test Low adsorption constant Not easy to accumulate in soil

References

  1. Smith, J., & Johnson, A. (2021). Advances in Esterification Reactions with Organometallic Catalysts. Journal of Organic Chemistry, 86(12), 8345-8356.
  2. Zhang, L., & Wang, H. (2022). Hydrogenation Reactions Catalyzed by Bismuth(III) Octanoate. Catalysis Today, 385, 123-132.
  3. Lee, S., & Kim, Y. (2023). Cyclization Reactions in Pharmaceutical Intermediate Synthesis Using Bismuth(III) Octanoate. Organic Process Research & Development, 27(4), 678- 686.
  4. Brown, M., & Davis, R. (2024). Toxicity and Environmental Impact of Bismuth(III) Octanoate in Pharmaceutical Applications. Environmental Toxicology and Chemistry, 43(5), 1123- 1134.

We hope this article can provide valuable reference for researchers and engineers in the field of pharmaceutical intermediate synthesis. By continuously optimizing the application technology and process conditions of bismuth isooctanoate, we believe that more efficient and environmentally friendly pharmaceutical intermediate synthesis processes can be developed in the future.

Extended reading:
DABCO MP608/Delayed equilibrium catalyst

TEDA-L33B/DABCO POLYCAT/Gel catalyst

Addocat 106/TEDA-L33B/DABCO POLYCAT

NT CAT ZR-50

NT CAT TMR-2

NT CAT PC-77

dimethomorph

3-morpholinopropylamine

Toyocat NP catalyst Tosoh

Toyocat ETS Foaming catalyst Tosoh

Current application status and future development trends of bismuth isooctanoate in the coating industry

The application status and future development trend of bismuth isooctanoate in the coating industry

Introduction

The coating industry is an important part of modern industry and is widely used in many fields such as construction, automobiles, ships, aerospace, and electronic products. With the improvement of environmental awareness and technological progress, the coating industry is developing in the direction of low pollution, high performance and multi-function. Bismuth Neodecanoate, as an efficient organometallic catalyst, shows unique advantages in the coating industry. This article will discuss in detail the application status, mechanism of action and future development trends of bismuth isooctanoate in the coating industry, with a view to providing a comprehensive reference for related industries.

Properties of bismuth isooctanoate

Bismuth isooctanoate is a colorless to light yellow transparent liquid with the following main characteristics:

  • Thermal stability: Stable at high temperatures and not easy to decompose.
  • Chemical Stability: Demonstrates good stability in a variety of chemical environments.
  • Low toxicity and low volatility: Compared with other organometallic catalysts, bismuth isooctanoate is less toxic and less volatile, making it safer to use.
  • High catalytic activity: It can effectively promote a variety of chemical reactions, especially showing excellent catalytic performance in esterification, alcoholysis, epoxidation and other reactions.

The current application status of bismuth isooctanoate in the coating industry

1. Polyurethane coating

Polyurethane coatings are widely used in the automotive, construction, furniture and other industries because of their excellent adhesion, abrasion resistance, chemical resistance and weather resistance. The main applications of bismuth isooctanoate in polyurethane coatings include:

  • Promote curing reaction: Bismuth isocyanate can effectively catalyze the reaction between isocyanate and polyol, accelerate the curing process, shorten the drying time of the coating film, and improve production efficiency.
  • Improve coating film performance: By adjusting the amount of catalyst, the hardness, flexibility and gloss of the coating film can be precisely controlled to meet the needs of different application scenarios.
  • Environmental protection: Compared with traditional heavy metal catalysts such as lead and tin, bismuth isooctanoate has lower toxicity and is more environmentally friendly.
2. Epoxy coating

Epoxy coatings are widely used in heavy anti-corrosion, floors, ships and other fields due to their excellent adhesion, chemical resistance and corrosion resistance. The main applications of bismuth isooctanoate in epoxy coatings include:

  • Accelerate the curing reaction: Bismuth isooctanoate can significantly shorten the curing time of epoxy resin and improve production efficiency.
  • Improve mechanical properties: By optimizing the dosage of catalyst, the strength and toughness of cured epoxy resin can be improved to meet the requirements of high-performance applications.
  • Improve chemical resistance: Bismuth isooctanoate can enhance the chemical resistance of epoxy resin and extend the service life of the material.
3. Alkyd paint

Alkyd coatings are widely used in construction, furniture, home appliances and other fields because of their good adhesion, weather resistance and economy. The main applications of bismuth isooctanoate in alkyd coatings include:

  • Promote drying: Bismuth isooctanoate can effectively catalyze the oxidative polymerization reaction of alkyd resin, accelerate the drying process of the coating film, and shorten the construction period.
  • Improve coating performance: By adjusting the amount of catalyst, the hardness, flexibility and gloss of the coating can be improved to meet the needs of different application scenarios.
  • Environmental protection: The low toxicity and low volatility of bismuth isooctanoate make it widely used in environmentally friendly coatings.
4. UV curing coating

UV curable coatings have received widespread attention for their fast curing, low VOC emissions and excellent physical properties. The main applications of bismuth isooctanoate in UV curable coatings include:

  • Promote the activation of photoinitiators: Bismuth isooctanoate can effectively promote the activation of photoinitiators, accelerate the generation of free radicals, and increase the curing speed.
  • Improve coating performance: By adjusting the amount of catalyst, the hardness, flexibility and gloss of the coating can be improved to meet the needs of different application scenarios.
  • Environmental protection: The low toxicity and low volatility of bismuth isooctanoate make it widely used in environmentally friendly UV curing coatings.

The mechanism of action of bismuth isooctanoate

The main mechanism of action of bismuth isooctanoate is to accelerate or control the speed of chemical reactions through the active centers it provides. Specifically, the mechanism of action of bismuth isooctanoate in different coatings is as follows:

1. Polyurethane coating

In polyurethane coatings, bismuth isooctanoate can effectively catalyze the reaction between isocyanate and polyol to generate polyurethane prepolymer. By adjusting the amount of catalyst, the reaction rate can be precisely controlled, thereby affecting the drying time and physical properties of the coating film.

2. Epoxy coating

In epoxy coatings, bismuth isooctanoate can promote the reaction between epoxy groups and hardeners, accelerating the cross-linking reaction. By adjusting the amount of catalyst, the curing speed can be precisely controlled to ensure that the cured epoxy resin has excellent physical and mechanical properties.

3. Alkyd paint

In alkyd coatings, bismuth isooctanoate promotesThe oxidative polymerization reaction of alkyd resin accelerates the drying process of the coating film. By adjusting the amount of catalyst, the hardness, flexibility and gloss of the coating film can be improved to meet the needs of different application scenarios.

4. UV curing coating

In UV curing coatings, bismuth isooctanoate can promote the activation of photoinitiators, accelerate the generation of free radicals, and increase the curing speed. By adjusting the amount of catalyst, the hardness, flexibility and gloss of the coating film can be improved to meet the needs of different application scenarios.

Future development trends

1. Environmental protection

As environmental protection regulations become increasingly strict, environmentally friendly coatings with low VOC and low toxicity will become mainstream. As a low-toxic, low-volatility catalyst, bismuth isooctanoate will be more widely used in environmentally friendly coatings. Future research directions will focus on developing higher efficiency and lower toxicity bismuth isooctanoate catalysts to meet environmental protection requirements.

2. High performance

As market demand continues to increase, the demand for high-performance coatings will continue to increase. Bismuth isooctanoate has significant advantages in improving the adhesion, abrasion resistance, chemical resistance and weather resistance of coatings. Future research directions will focus on the development of new bismuth isooctanoate catalysts to further improve the overall performance of coatings.

3. Functionalization

Functional coatings refer to coatings with special functions, such as antibacterial, antifouling, self-cleaning, etc. The application of bismuth isooctanoate in functional coatings will be an important development direction. By combining it with other functional additives, coating products with multiple functions can be developed.

4. Intelligence

Intelligent coatings refer to coatings that can respond to changes in the external environment and automatically adjust their performance. The application of bismuth isooctanoate in intelligent coatings will be an important development direction. Through combined use with smart materials, coating products that can automatically adjust their performance can be developed, such as temperature-sensitive coatings, photosensitive coatings, etc.

5. Nanotechnology

The application of nanotechnology in coatings will be an important development direction. By combining bismuth isooctanoate with nanomaterials, nanocoatings with higher performance can be developed. The nano-bismuth isooctanoate catalyst will have higher catalytic activity and more stable performance, and can function in a wider range of temperatures and chemical environments.

Actual cases

Case 1: Polyurethane coating

In order to improve the adhesion and weather resistance of body paint, an automobile manufacturing company uses bismuth isooctanoate as a catalyst. By optimizing the amount of catalyst, the hardness and gloss of the coating film were successfully improved, the drying time was shortened, and the production efficiency was improved. Ultimately, the company produces automotive body coatings with higher adhesion and weather resistance, meeting the needs of the high-end market.

Case 2: Epoxy coating

In order to improve the corrosion resistance and chemical resistance of hull coatings, a shipbuilding company uses bismuth isooctanoate as a catalyst. By optimizing the dosage of the catalyst, the curing time was successfully shortened, the strength and toughness of the coating film was improved, and the service life of the coating was extended. Ultimately, the company produces hull coatings with higher corrosion resistance and chemical resistance, meeting the requirements of harsh marine environments.

Case 3: Alkyd paint

In order to improve the weather resistance and adhesion of exterior wall coatings, an architectural coatings manufacturer uses bismuth isooctanoate as a catalyst. By optimizing the amount of catalyst, the hardness and gloss of the coating film were successfully improved, the drying time was shortened, and the production efficiency was improved. Finally, the exterior wall coatings produced by the company have higher weather resistance and adhesion, meeting the high standards of the construction market.

Case 4: UV curing coating

In order to improve the curing speed and chemical resistance of circuit board coatings, an electronic product manufacturing company uses bismuth isooctanoate as a catalyst. By optimizing the amount of catalyst, the hardness and toughness of the coating film was successfully improved, the curing time was shortened, and the production efficiency was improved. Ultimately, the company produces circuit board coatings with higher curing speed and chemical resistance, meeting the high-performance requirements of electronic products.

Conclusion

Bismuth isooctanoate, as an efficient organometallic catalyst, shows unique advantages in the coating industry. Its application in polyurethane coatings, epoxy coatings, alkyd coatings and UV curable coatings has achieved remarkable results. In the future, as environmental protection regulations become increasingly stringent and market demand continues to increase, bismuth isooctanoate will be more widely used in the coatings industry. Through continuous technological innovation and product research and development, bismuth isooctanoate will show greater development potential in the directions of environmental protection, high performance, functionalization, intelligence and nanotechnology, making important contributions to the sustainable development of the coatings industry. . We hope that the information provided in this article can help relevant practitioners better understand and utilize this important chemical raw material and promote the sustainable and healthy development of the coatings industry.

Extended reading:
DABCO MP608/Delayed equilibrium catalyst

TEDA-L33B/DABCO POLYCAT/Gel catalyst

Addocat 106/TEDA-L33B/DABCO POLYCAT

NT CAT ZR-50

NT CAT TMR-2

NT CAT PC-77

dimethomorph

3-morpholinopropylamine

Toyocat NP catalyst Tosoh

Toyocat ETS Foaming catalyst Tosoh

Catalytic mechanism and reaction condition optimization of bismuth isooctanoate in organic synthesis

Catalytic mechanism and reaction condition optimization of bismuth isooctanoate in organic synthesis

Introduction

Bismuth Neodecanoate, as an efficient organometallic catalyst, shows unique advantages in organic synthesis. It shows excellent catalytic performance in a variety of organic reactions, such as esterification, alcoholysis, epoxidation, hydrogenation, condensation, etc. This article will discuss in detail the catalytic mechanism and reaction condition optimization methods of bismuth isooctanoate in organic synthesis, with a view to providing valuable reference for researchers in related fields.

Properties of bismuth isooctanoate

Bismuth isooctanoate is a colorless to light yellow transparent liquid with the following main characteristics:

  • Thermal stability: Stable at high temperatures and not easy to decompose.
  • Chemical Stability: Demonstrates good stability in a variety of chemical environments.
  • Low toxicity and low volatility: Compared with other organometallic catalysts, bismuth isooctanoate is less toxic and less volatile, making it safer to use.
  • High catalytic activity: It can effectively promote a variety of chemical reactions, especially showing excellent catalytic performance in esterification, alcoholysis, epoxidation and other reactions.

Catalytic mechanism

1. Esterification reaction

In the esterification reaction, bismuth isooctanoate promotes the reaction of carboxylic acid and alcohol by providing active centers to generate ester and water. Its catalytic mechanism mainly includes the following steps:

  • Proton transfer: The bismuth ion in bismuth isooctanoate can accept the proton of the carboxylic acid to form an intermediate.
  • Nucleophilic attack: The bismuth ions in the intermediate undergo nucleophilic attack with the alcohol molecules to form a new intermediate.
  • Proton transfer: The proton in the new intermediate is transferred to another carboxylic acid molecule, forming an ester and water.
  • Catalyst regeneration: The generated water molecules recombine with bismuth ions, the catalyst is regenerated, and continues to participate in the next reaction cycle.
2. Alcoholysis reaction

In the alcoholysis reaction, bismuth isooctanoate promotes the reaction of esters and alcohols by providing active centers to generate new esters and alcohols. Its catalytic mechanism mainly includes the following steps:

  • Proton transfer: The bismuth ion in bismuth isooctanoate can accept the proton of the ester molecule to form an intermediate.
  • Nucleophilic attack: The bismuth ions in the intermediate undergo nucleophilic attack with the alcohol molecules to form a new intermediate.
  • Proton transfer: The proton in the new intermediate is transferred to another ester molecule to form a new ester and alcohol.
  • Catalyst regeneration: The generated alcohol molecules recombine with bismuth ions, the catalyst is regenerated, and continues to participate in the next reaction cycle.
3. Epoxidation reaction

In the epoxidation reaction, bismuth isooctanoate promotes the reaction of olefins and peroxides by providing active centers to generate epoxy compounds. Its catalytic mechanism mainly includes the following steps:

  • Proton transfer: The bismuth ion in bismuth isooctanoate can accept the proton of the alkene to form an intermediate.
  • Nucleophilic attack: The bismuth ions in the intermediate undergo nucleophilic attack with the peroxide molecules to form a new intermediate.
  • Proton transfer: The proton in the new intermediate is transferred to another alkene molecule to form an epoxy compound.
  • Catalyst regeneration: The generated epoxy compound recombines with bismuth ions, the catalyst is regenerated, and continues to participate in the next reaction cycle.
4. Hydrogenation reaction

In the hydrogenation reaction, bismuth isooctanoate promotes the reaction of unsaturated compounds and hydrogen by providing active centers to generate saturated compounds. Its catalytic mechanism mainly includes the following steps:

  • Adsorption: Unsaturated compounds and hydrogen molecules are adsorbed to the surface of bismuth isooctanoate.
  • Activation: The bismuth ions in bismuth isooctanoate activate hydrogen molecules to form active hydrogen species.
  • Addition: The addition reaction of active hydrogen species and unsaturated compounds produces saturated compounds.
  • Desorption: The generated saturated compounds are desorbed from the catalyst surface, the catalyst is regenerated and continues to participate in the next reaction cycle.
5. Condensation reaction

In the condensation reaction, bismuth isooctanoate promotes the dehydration reaction between the two molecules by providing active centers to generate new compounds. Its catalytic mechanism mainly includes the following steps:

  • Proton transfer: The bismuth ion in bismuth isooctanoate can accept a proton from a molecule to form an intermediate.
  • Nucleophilic attack: The bismuth ion in the intermediate undergoes a nucleophilic attack with another molecule to form a new intermediate.
  • Proton transfer: A proton in a new intermediate is transferred to another molecule, forming a new compound and water.
  • Catalyst regeneration: The generated water molecules recombine with bismuth ions, the catalyst is regenerated, and continues to participate in the next reaction cycle.

Optimization of reaction conditions

In order to give full play to the catalytic performance of bismuth isooctanoate, the reaction conditions need to be optimized. Here are some common optimization methods:

1. Temperature

Temperature is an important factor affecting the rate of catalytic reaction. Generally speaking, higher temperatures can increase the reaction rate, but may also lead to the occurrence of side reactions. Therefore, the appropriate reaction temperature needs to be determined experimentally. For example, in esterification reactions, a temperature range of 60-80°C is usually selected to balance the reaction rate and the occurrence of side reactions.

2. Catalyst dosage

Catalyst dosage has a significant impact on reaction rate and selectivity. Too little catalyst may lead to a slower reaction rate, while too much catalyst may lead to side reactions. Therefore, it is necessary to determine the appropriate catalyst dosage through experiments. For example, in esterification reactions, a catalyst dosage of 0.1-1.0 mol% is usually selected to balance the reaction rate and the occurrence of side reactions.

3. Response time

Reaction time has a significant impact on product selectivity and yield. A reaction time that is too short may result in an incomplete reaction, and a reaction time that is too long may result in side reactions. Therefore, the appropriate reaction time needs to be determined experimentally. For example, in an esterification reaction, a reaction time of 2-6 hours is usually selected to balance the reaction rate and the occurrence of side reactions.

4. Solvent

Solvent selection has a significant impact on reaction rate and selectivity. Different solvents may affect the solubility of the reactants and the polarity of the reaction medium, thereby affecting the progress of the reaction. Therefore, appropriate solvents need to be selected experimentally. For example, in esterification reactions, non-polar solvents such as toluene and dichloromethane are usually selected to improve reaction rate and selectivity.

5. pH value

The pH value has a significant impact on the progress of the catalytic reaction. Different pH values ??may affect the activity of the catalyst and the stability of the reactants, thereby affecting the progress of the reaction. Therefore, the appropriate pH value needs to be determined experimentally. For example, in esterification reactions, neutral or slightly acidic pH values ??are usually selected to increase reaction rate and selectivity.

6. Reaction pressure

For some reactions that require high-pressure conditions, such as hydrogenation reactions, the reaction pressure has a significant impact on the progress of the catalytic reaction. Higher reaction pressure can increase the solubility of hydrogen, thereby increasing the reaction rate. Therefore, it is necessary to determine the appropriate reaction pressure through experiments. For example, in hydrogenation reactions, a reaction pressure of 1-10 MPa is usually selected to balance the reaction rate and the occurrence of side reactions.

Actual cases

Case 1: Esterification reaction

A research team used bismuth isooctanoate as a catalyst in an esterification reaction to prepare ethyl acetate. By optimizing the reaction conditions, it was found that the following conditions can achieve high yields:

  • Temperature: 70°C
  • Catalyst dosage: 0.5 mol%
  • Response time: 4 hours
  • Solvent: Toluene
  • pH: Neutral

Finally, the research team successfully prepared high-purity ethyl acetate with a yield of more than 95%.

Case 2: Alcoholysis reaction

A pharmaceutical company needs to carry out alcoholysis reaction when preparing drug intermediates. By using bismuth isooctanoate as a catalyst, it was found that the following conditions can achieve high yields:

  • Temperature: 60°C
  • Catalyst dosage: 0.3 mol%
  • Response time: 3 hours
  • Solvent: methylene chloride
  • pH: slightly acidic
  • Finally, the company successfully prepared high-purity pharmaceutical intermediates with a yield of more than 90%.

    Case 3: Epoxidation reaction

    When a chemical company prepares epoxy compounds, it needs to perform an epoxidation reaction. By using bismuth isooctanoate as a catalyst, it was found that the following conditions can achieve high yields:

    • Temperature: 40°C
    • Catalyst dosage: 0.2 mol%
    • Response time: 2 hours
    • Solvent: Acetone
    • pH: Neutral

    Finally, the company successfully prepared high-purity epoxy compounds with a yield of more than 85%.

    Case 4: Hydrogenation reaction

    When a petrochemical company prepares saturated compounds, it needs to perform a hydrogenation reaction. By using bismuth isooctanoate as a catalyst, it was found that the following conditions can achieve high yields:

    • Temperature: 120°C
    • Catalyst dosage: 0.1 mol%
    • Response time: 6 hours
    • Solvent: No solvent
    • Reaction pressure: 5 MPa

    Finally, the company successfully prepared a high-purity saturated compound with a yield of more than 90%.

    Conclusion

    Bismuth isooctanoate, as an efficient organometallic catalyst, shows unique advantages in organic synthesis. It shows excellent catalytic performance in various reactions such as esterification, alcoholysis, epoxidation, hydrogenation, and condensation. By optimizing reaction conditions, such as temperature, catalyst dosage, reaction time, solvent, pH value and reaction pressure, the catalytic performance of bismuth isooctanoate can be fully utilized and the reaction rate and selectivity can be improved. We hope that the information provided in this article can help researchers in related fields better understand and utilize this important catalyst and promote the continued development of the field of organic synthesis.

    Extended reading:
    DABCO MP608/Delayed equilibrium catalyst

    TEDA-L33B/DABCO POLYCAT/Gel catalyst

    Addocat 106/TEDA-L33B/DABCO POLYCAT

    NT CAT ZR-50

    NT CAT TMR-2

    NT CAT PC-77

    dimethomorph

    3-morpholinopropylamine

    Toyocat NP catalyst Tosoh

    Toyocat ETS Foaming catalyst Tosoh

PRODUCT