Cyclohexene (C6H10) is a cyclic hydrocarbon with a double bond, commonly used as a solvent and intermediate in chemical reactions due to its reactivity and versatility.
| IUPAC Name | Cyclohexene |
| Molecular Formula | C₆H₁₀ |
| CAS Number | 110-83-8 |
| Synonyms | Monocyclohexene, Hexanaphthene, 1,2-dihydrobenzene |
| InChI | InChI=1S/C6H10/c1-2-4-6-5-3-1/h1-2H,3-6H2 |
Cyclohexene Properties
Cyclohexene Formula
The formula for cyclohexene is C₆H₁₀, representing its molecular composition. It consists of six carbon atoms arranged in a ring, with each carbon atom bonded to two hydrogen atoms. This cyclic structure gives cyclohexene its unique properties and reactivity.
Cyclohexene Molar Mass
The molar mass of monocyclohexene can be calculated by summing up the atomic masses of its constituent elements. It is determined by adding the atomic masses of six carbon atoms (12.01 g/mol each) and ten hydrogen atoms (1.008 g/mol each). Thus, the molar mass of monocyclohexene is approximately 82.14 g/mol.
Cyclohexene Boiling Point
Monocyclohexene exhibits a relatively low boiling point of around 83-85°C (181-185°F). This low boiling point makes it suitable for various applications as a solvent or reaction intermediate. The relatively low boiling point allows for easy separation and recovery of monocyclohexene during various industrial processes.
Cyclohexene Melting Point
The melting point of monocyclohexene is approximately -104 to -103°C (-155 to -153°F). This low melting point enables monocyclohexene to exist in a liquid state at room temperature and facilitates its use as a reactant or solvent in a wide range of chemical reactions and processes.
Cyclohexene Density g/mL
Monocyclohexene has a density of around 0.81-0.83 g/mL at room temperature. This density value indicates that monocyclohexene is less dense than water, allowing it to float on the surface of the water. The density of monocyclohexene plays a crucial role in determining its behavior in various industrial and laboratory applications.
Cyclohexene Molecular Weight
The molecular weight of monocyclohexene, which is the sum of the atomic weights of all atoms in a molecule, is approximately 82.14 g/mol. This molecular weight value is essential for calculating stoichiometry, determining reactant quantities, and understanding the physical and chemical properties of monocyclohexene.
Cyclohexene Structure
Monocyclohexene has a unique molecular structure characterized by a six-membered carbon ring with a double bond between two adjacent carbon atoms. This structure imparts both stability and reactivity to monocyclohexene, making it a versatile compound in various chemical reactions and organic synthesis.
Cyclohexene Solubility
Monocyclohexene exhibits limited solubility in water due to its nonpolar nature. However, it is highly soluble in organic solvents like ethanol, acetone, and ether. This solubility behavior allows monocyclohexene to be easily mixed and dissolved in organic solvents, enhancing its application as a reactant or solvent in various processes.
| Appearance | Colorless |
| Specific Gravity | 0.81-0.83 |
| Color | Colorless |
| Odor | Sweet, Ether-like |
| Molar Mass | 82.14 g/mol |
| Density | 0.81-0.83 g/mL |
| Melting Point | -104 to -103°C |
| Boiling Point | 83-85°C |
| Flash Point | -7°C |
| Water Solubility | Insoluble |
| Solubility | Soluble in organic solvents |
| Vapour Pressure | 184 mmHg |
| Vapour Density | 2.9 (air = 1) |
| pKa | ~15.5 |
| pH | Not applicable |
Cyclohexene Safety and Hazards
Monocyclohexene poses certain safety hazards and precautions must be taken when handling it. It is flammable and can ignite at low temperatures. When working with monocyclohexene, it is important to ensure adequate ventilation to prevent the accumulation of vapors. Direct contact with the liquid or vapor should be avoided as it may cause irritation to the skin, eyes, and respiratory system. Prolonged or repeated exposure may lead to adverse health effects. In case of ingestion or inhalation, immediate medical attention is necessary. It is crucial to follow proper storage and handling procedures, including the use of appropriate personal protective equipment, to minimize potential risks associated with monocyclohexene.
| Hazard Symbols | Xi |
| Safety Description | May cause skin and eye irritation. Flammable liquid and vapor. |
| UN IDs | UN 2256, UN 2257 |
| HS Code | 2902.19.0000 |
| Hazard Class | 3 (Flammable liquid) |
| Packing Group | III (Low danger) |
| Toxicity | May cause adverse health effects with prolonged or repeated exposure. |
Cyclohexene Synthesis Methods
Various methods can synthesize monocyclohexene.
One common method is the catalytic dehydrogenation of cyclohexanol, which involves the use of a catalyst such as copper or platinum. The catalyst facilitates the removal of hydrogen atoms when heating cyclohexanol to high temperatures, resulting in the formation of monocyclohexene.
Another method is the elimination reaction of cyclohexanol with a strong acid, such as sulfuric acid or phosphoric acid. The acid catalyst promotes the removal of a water molecule from cyclohexanol, leading to the formation of monocyclohexene.
Furthermore, the pyrolysis of cyclohexanol or cyclohexylamine yields monocyclohexene. Pyrolysis involves subjecting the starting material to high temperatures in the absence of oxygen, causing the breakdown of molecular bonds and the formation of monocyclohexene.
Oxidizing agents such as chromium trioxide or potassium permanganate oxidize cyclohexane to synthesize monocyclohexene. This oxidation reaction converts cyclohexane into monocyclohexene by introducing a double bond into the carbon ring.
Each of these methods offers distinct advantages depending on the specific requirements of the synthesis. To achieve high yields and desired product purity in the synthesis of monocyclohexene, one must carefully consider reaction conditions, catalysts, and purification techniques.
Cyclohexene Uses
Monocyclohexene finds various applications due to its unique properties and reactivity. Here are some key uses of monocyclohexene:
- Solvent: Monocyclohexene serves as a versatile solvent in numerous chemical reactions, particularly those involving nonpolar or slightly polar compounds. It dissolves oils, resins, waxes, and other organic substances commonly.
- Intermediate in Chemical Synthesis: Monocyclohexene plays a crucial role as an intermediate in synthesizing various chemicals, including adipic acid, a key component used in the production of nylon. It also serves as a precursor for the synthesis of cyclohexanol and cyclohexanone.
- Polymerization: Poly(monocyclohexene), a polymer with applications in coatings, adhesives, and elastomers, uses monocyclohexene as a monomer in its production.
- Organic Reactions: Monocyclohexene participates in a wide range of organic reactions, such as cycloadditions, oxidation, and reduction reactions. It is particularly useful in the formation of cyclic compounds and as a reactant in the synthesis of pharmaceuticals, fragrances, and flavors.
- Extraction and Purification: In the purification of natural products, including plant extracts, essential oils, and flavors, researchers utilize monocyclohexene as an extraction solvent. Its low boiling point allows for easy separation from the extracted compounds.
- Research and Laboratory Applications: Monocyclohexene serves as a valuable reagent in laboratory settings for various experiments and reactions due to its stability, reactivity, and solvency properties.
The diverse range of applications of monocyclohexene highlights its significance in the chemical industry, research laboratories, and various manufacturing processes.
Questions:
Q: What compound is produced when cyclohexene is treated with concentrated KMnO4?
A: When monocyclohexene is treated with concentrated KMnO4, the compound cyclohexanone is produced.
Q: How could you distinguish between cyclohexane and cyclohexene using IR?
A: Cyclohexane and monocyclohexene can be distinguished using IR spectroscopy by examining the presence or absence of a characteristic C=C stretching peak around 1630-1670 cm^-1 in the spectrum of monocyclohexene.
Q: Is cyclohexene aromatic?
A: No, monocyclohexene is not aromatic. It is a cyclic compound with a double bond, but it does not possess the necessary criteria to be considered aromatic.
Q: How many possible stereoisomers exist for the bromination of cyclohexene?
A: There are two possible stereoisomers (cis and trans) for the bromination of monocyclohexene, resulting from the addition of bromine to the double bond.
Q: An unsaturated product results from the reaction of cyclohexene with which of these?
A: An unsaturated product results from the reaction of monocyclohexene with a dienophile in a Diels-Alder reaction.
Q: How to find the percent yield of cyclohexene?
A: The percent yield of monocyclohexene can be calculated by dividing the actual yield of monocyclohexene by the theoretical yield, then multiplying by 100%.
Q: How to convert cyclopentyl methan-1-ol to cyclohexene?
A: Cyclopentyl methan-1-ol can be converted to monocyclohexene by subjecting it to dehydration, typically using an acidic catalyst such as concentrated sulfuric acid or phosphoric acid.