Organic chemistry is a complex field that requires a deep understanding of various chemical compounds and their properties. One such compound that has gained significant attention in recent years is 1-heptyne. This molecule is a member of the alkyne family and has unique properties that make it an essential component in various chemical reactions.
This article will explore the potential of 1-heptyne and its significance in organic chemistry. Whether you are a student, researcher, or a professional in the field, this comprehensive guide will provide you with valuable insights into this fascinating compound.
What is 1-Heptyne?
1-Heptyne is a chemical compound with the molecular formula C7H12 and a linear structure. It is commonly used as a basic building block in synthesizing complex acetylenic molecules in various industries, including perfumery, agrochemical and pharmaceutical.
The molecule’s structure includes an arrangement of atoms held together by chemical bonds. It is soluble in organic solvents and its suppliers include Anbu Chemicals. Recommendations for usage levels of 1-heptyne vary depending on the industry, but it is not typically recommended for fragrance use.
1-Heptyne Chemical Properties
|clear colorless to light yellow-green liquid
|-81 °C (lit.)
|99-100 °C (lit.)
|0.733 g/mL at 25 °C (lit.)
|Soluble in organic solvents. Insoluble in water.
|25, 100 mL in glass bottle
What is the use of 1-Heptyne?
1-Heptyne can be used in the synthesis of fatty acids, specifically for the production of (6Z,10E,12Z)-octadeca-6,10,12-trienoic acid and (8Z,12E,14Z)-eicosa-8,12,14-trienoic acid, which are omega-3 and omega-6 essential fatty acids commonly found in fish oil and other dietary supplements.
Preparing 1-Heptyne through dehalogenation methods using 1,2-dibromoalkanes under PTC conditions is also valid. PTC stands for phase-transfer catalysis, a technique that facilitates reactions between two immiscible phases, such as an organic and aqueous phase.
There are no significant industrial or commercial applications for 1-Heptyne outside its use in fatty acid synthesis. It is not commonly used in fragrances or flavors due to its strong and unpleasant odor.
What are the synthesis methods for 1-Heptyne?
Several methods have been developed to synthesize 1-heptyne, which can be categorized into traditional and advanced methods. Below are the different synthesis methods, including their respective yields, costs, and scalability.
Traditional methods of synthesis 1-Heptyne
Dehydrohalogenation is a traditional method for synthesizing 1-heptyne, involving the elimination of hydrogen halide (HX) from a suitable precursor. The general reaction is as follows:
R-CH2-CH2-X → R-CH≡CH + HX
For the synthesis of 1-heptyne, a precursor such as 1-bromo-2-heptene or 1-chloro-2-heptene can be used. Treatment with a strong base, like sodium amide (NaNH2), results in the dehydrohalogenation of the precursor to form 1-heptyne.
Metal Acetylides with Alkyl Halides
Metal acetylides, formed by a reaction between an alkali metal and an alkyne, can synthesize 1-heptyne. The general reaction is as follows:
RC≡C-M + R'-X → RC≡C-R' + MX
To synthesize 1-heptyne, ethynylmagnesium bromide (HC≡C-MgBr) can be reacted with 1-bromoheptane to yield the desired product.
Advanced methods of synthesis 1-Heptyne
Transition Metal-Catalyzed Alkyne Metathesis
Transition metal-catalyzed alkyne metathesis is an advanced method for synthesizing 1-heptyne. This reaction involves the redistribution of alkyne carbon-carbon triple bonds in the presence of a transition metal catalyst, such as molybdenum or tungsten alkylidyne complexes. Using appropriate alkyne substrates, 1-heptyne can be obtained as one of the products.
Sonogashira coupling is a palladium-catalyzed cross-coupling reaction between terminal alkynes and aryl or vinyl halides. The general reaction is as follows:
R-X + R'-C≡CH → R-C≡C-R' + HX
For the synthesis of 1-heptyne, the reaction between ethyne and 1-bromoheptane, catalyzed by a palladium(0) complex, can be performed.
Comparison of the Methods (Yield, Cost, Scalability)
- Dehydrohalogenation: This method typically provides moderate to good yields of 1-heptyne but requires a strong base and a suitable precursor, which may be costly or difficult to obtain. The reaction can be scaled up but may become less efficient due to the requirement of stoichiometric amounts of base.
- Metal Acetylides with Alkyl Halides: This method generally provides good to excellent yields of 1-heptyne. However, the reaction requires alkyl halides and organometallic reagents, which can be expensive and sensitive to air and moisture. Scalability might be limited due to the sensitivity of the reagents.
- Transition Metal-Catalyzed Alkyne Metathesis: This method can provide high yields of 1-heptyne, the reaction may require expensive transition metal catalysts and specific reaction conditions. Scalability is possible but may be limited by the cost of the catalysts.
- Sonogashira Coupling: This method typically provides high yields of 1-heptyne with excellent functional group tolerance. However, the reaction requires a palladium catalyst, which can be expensive. The reaction is generally considered scalable and can be conducted under relatively mild conditions, making it suitable for industrial applications.
What are the benefits and limitations of using 1-Heptyne?
One of the main benefits of using 1-heptyne in chemical reactions is that it can be used as a starting material for many different syntheses. Due to its versatile nature, this compound can create other important compounds such as alcohols, carboxylic acids, and even amines. This makes 1-heptyne an extremely valuable component in organic synthesis laboratories.
Another benefit of working with 1-heptyne is its relatively low cost compared to alternatives. Since it is relatively inexpensive, chemists can save money while still being able to acquire quality materials for their experiments. 1-heptyne is also very stable and has a long shelf life which further helps reduce costs associated with storing and disposing unused materials.
However, some challenges and limitations are associated with working with 1-hepytyne. Firstly, since 1-heptyne contains three carbon atoms in its structure, it has difficulty forming soluble compounds with many large molecules making it difficult to use in certain reactions or purifications.
Additionally, this compound can be highly reactive meaning that special precautions need to be taken when dealing with it to avoid unwanted side reactions during synthesis or purification processes. Lastly, since this compound’s structure is relatively complex compared to other chemicals used in synthetic reactions, successful purifications may require several steps that can take extra time and resources.
Applications of 1-Heptyne in organic chemistry
1-Heptyne as a building block
1-Heptyne is used as a building block for constructing larger and more complex organic molecules. It can undergo various reactions to produce useful synthetic intermediates.
1-Heptyne can undergo alkylation reactions with alkyl halides to produce longer chain alkyl alkynes which have applications as synthetic lubricants.
1-Heptyne participates in cycloaddition reactions like Diels-Alder reaction to produce cyclooctene derivatives which are useful synthetic intermediates.
1-Heptyne undergoes cross-coupling reactions like Sonogashira coupling and Cadiot-Chodkiewicz reaction to produce conjugated enynes and diynes respectively which have applications in materials science.
1-Heptyne in polymerization
1-Heptyne can be polymerized to produce polyacetylene derivatives with extended conjugated pi systems.
1-Heptyne undergoes free radical polymerization using radical initiators to produce high molecular weight polymers.
Transition metal-catalyzed polymerization
1-Heptyne can be polymerized using transition metal catalysts like rhodium, ruthenium, etc. to produce polyacetylene derivatives in a controlled manner.
Bioactive compounds derived from 1-Heptyne
1-Heptyne is used as a starting material for synthesizing many bioactive molecules.
Some drug molecules like Mintop and Anacetrapib are synthesized starting from 1-heptyne.
A few agrochemicals like Piricyplex and Fluroxypyr are derived from 1-heptyne.
Some natural product syntheses like that of Faranal, Germacrene D, etc. utilize 1-heptyne as a starting material.
Safety and environmental considerations of 1-Heptyne
Handling and storage of 1-heptyne
- 1-Heptyne is a highly flammable liquid and vapor. It should be handled and stored carefully away from sources of ignition.
- It should be stored in ventilated areas away from oxidizing agents and acids.
- Containers should be adequately sealed and grounded to prevent static charge build up.
Safety precautions in the laboratory and industry
- Proper ventilation, protective equipment like goggles, gloves and fire extinguishers should be present.
- Open flames and sparks should be avoided.
- In case of fire, use carbon dioxide, dry chemical or alcohol-resistant foam for extinguishing. Water spray can be used to cool and disperse vapors.
- Spillage should be contained using sand, earth or other non-combustible absorbent material.
- Ingestion or inhalation of 1-heptyne can be hazardous. In case of exposure, seek medical help immediately.
Environmental impact and regulations
- 1-Heptyne is classified as a marine pollutant and hazardous to the aquatic environment. Its release to the environment should be minimized.
- It is listed under many regulations like TSCA, DSL, etc. due to its hazardous nature.
- According to the IARC, 1-heptyne is not classified as carcinogenic to humans. However, extensive exposure may cause central nervous system depression.
- The waste disposal of 1-heptyne should be done according to environmental regulations. It should not be drained or thrown in the environment.
- Spillage or uncontrolled releases of 1-heptyne into the environment should be reported to the local agencies immediately.
- The use and sale of 1-heptyne is regulated in many countries due to its hazardous and flammable nature. Proper licenses and permits are required for production, transportation, storage and sale.
In conclusion, 1-heptyne is a valuable compound in organic chemistry that offers various possibilities for research and industry. Its unique properties and reactivity make it a versatile building block for synthesizing various compounds. As highlighted in this comprehensive guide, unlocking the potential of 1-heptyne requires a thorough understanding of its properties and reaction mechanisms.
Therefore, we encourage researchers and industry professionals to explore the potential of 1-heptyne in their work and take advantage of its versatility in organic synthesis. By doing so, we can continue to advance the field of organic chemistry and develop new and innovative products.