Cis 1 tert butyl 3 methylcyclohexane is a versatile organic compound with a wide range of properties and applications. Its unique structure and reactivity make it an important intermediate in organic synthesis and a valuable solvent in various industries.
This comprehensive guide delves into the physical and chemical properties, synthesis methods, reactivity, applications, safety considerations, and spectroscopic analysis of cis 1 tert butyl 3 methylcyclohexane, providing a thorough understanding of this fascinating compound.
Properties
Cis 1 tert butyl 3 methylcyclohexane, an organic compound, exhibits distinct physical and chemical properties that define its behavior and applications.
Physically, it is a colorless liquid with a characteristic odor. Its molecular weight is 156.27 g/mol, and its density is approximately 0.81 g/cm 3at 25 °C. It has a boiling point of 168-170 °C and a melting point of -77 °C.
Chemically, cis 1 tert butyl 3 methylcyclohexane is a saturated hydrocarbon, meaning it contains only single bonds between its carbon atoms. The tert-butyl group (-C(CH 3) 3) attached to carbon 1 and the methyl group (-CH 3) attached to carbon 3 impart unique characteristics to the molecule.
The presence of the tert-butyl group introduces steric hindrance around carbon 1, influencing the reactivity and selectivity of the molecule. The methyl group contributes to the overall shape and hydrophobic nature of the compound.
Physical Properties
- Color: Colorless liquid
- Odor: Characteristic odor
- Molecular weight: 156.27 g/mol
- Density: 0.81 g/cm 3(at 25 °C)
- Boiling point: 168-170 °C
- Melting point: -77 °C
Chemical Properties
- Saturated hydrocarbon (contains only single bonds between carbon atoms)
- Steric hindrance due to the tert-butyl group at carbon 1
- Hydrophobic nature due to the methyl group at carbon 3
Comparison to Similar Compounds
The table below compares the properties of cis 1 tert butyl 3 methylcyclohexane with those of other similar compounds:
| Property | Cis 1 tert butyl 3 methylcyclohexane | Cyclohexane | tert-Butylbenzene |
|---|---|---|---|
| Molecular weight (g/mol) | 156.27 | 84.16 | 134.22 |
| Density (g/cm3) | 0.81 | 0.77 | 0.86 |
| Boiling point (°C) | 168-170 | 81 | 169 |
| Melting point (°C) | -77 | 6.5 | -55 |
Synthesis
The synthesis of cis-1-tert-butyl-3-methylcyclohexane can be achieved through various methods. One common approach involves the alkylation of 1-tert-butylcyclohexene with methylmagnesium bromide, followed by hydrogenation of the resulting alkene.
Alkylation of 1-tert-butylcyclohexene
In this step, 1-tert-butylcyclohexene reacts with methylmagnesium bromide (CH 3MgBr) in an ether solvent, such as diethyl ether or tetrahydrofuran (THF). The reaction proceeds via a nucleophilic attack of the Grignard reagent on the double bond of the cyclohexene, resulting in the formation of a new carbon-carbon bond and the addition of a methyl group to the molecule.
CH3MgBr + 1-tert-butylcyclohexene → CH 3-1-tert-butylcyclohexene + MgBr 2
Hydrogenation of the alkene
The resulting alkene intermediate is then subjected to hydrogenation in the presence of a catalyst, such as palladium or platinum, to convert the double bond into a single bond. This step saturates the molecule and yields the desired cis-1-tert-butyl-3-methylcyclohexane product.
CH3-1-tert-butylcyclohexene + H 2→ cis-1-tert-butyl-3-methylcyclohexane
Reactions
cis-1-tert-butyl-3-methylcyclohexane is a highly reactive compound that undergoes a variety of reactions, including addition, substitution, and elimination reactions.
The tert-butyl group is a good electron-donating group, which makes the cyclohexane ring more reactive towards electrophilic addition reactions.
Addition Reactions, Cis 1 tert butyl 3 methylcyclohexane
- cis-1-tert-butyl-3-methylcyclohexane reacts with bromine in the presence of light to form 1,2-dibromide.
- It also reacts with hydrogen in the presence of a catalyst to form cis-1-tert-butyl-3-methylcyclohexane.
Substitution Reactions
- cis-1-tert-butyl-3-methylcyclohexane reacts with chlorine in the presence of light to form 1-chloro-1-tert-butyl-3-methylcyclohexane.
- It also reacts with nitric acid in the presence of sulfuric acid to form 1-nitro-1-tert-butyl-3-methylcyclohexane.
Elimination Reactions
- cis-1-tert-butyl-3-methylcyclohexane reacts with potassium tert-butoxide in the presence of heat to form isobutylene.
- It also reacts with sodium hydroxide in the presence of heat to form cyclohexene.
Applications
Cis 1 tert butyl 3 methylcyclohexane finds applications in various industries and research domains.
One significant application lies in organic synthesis, where it serves as an intermediate in the production of more complex organic compounds. Its unique structural features, including the tert-butyl and methyl groups, make it a versatile building block for a wide range of chemical reactions.
As an Intermediate in Organic Synthesis
Cis 1 tert butyl 3 methylcyclohexane is a valuable intermediate in the synthesis of various organic compounds, including pharmaceuticals, fragrances, and flavors. Its reactivity allows for diverse chemical transformations, such as alkylation, oxidation, and cycloaddition reactions.
For instance, it can be used to synthesize more complex cyclohexane derivatives through Diels-Alder reactions. Additionally, its tert-butyl group can undergo Friedel-Crafts alkylation to introduce additional functional groups.
As a Solvent
Cis 1 tert butyl 3 methylcyclohexane is also employed as a solvent in various chemical processes. Its non-polar nature and low volatility make it suitable for dissolving organic compounds with similar properties.
It is commonly used in extraction and purification processes, as well as in the synthesis of organometallic compounds. Its ability to dissolve both polar and non-polar compounds makes it a versatile solvent for a wide range of applications.
Safety and Handling: Cis 1 Tert Butyl 3 Methylcyclohexane
Cis 1 tert butyl 3 methylcyclohexane is a flammable liquid with a flash point of 36 °C. It is also harmful if swallowed, inhaled, or absorbed through the skin. Therefore, it is important to take appropriate safety precautions when handling this chemical.
When handling cis 1 tert butyl 3 methylcyclohexane, it is important to wear appropriate personal protective equipment (PPE), including gloves, a lab coat, and a respirator. It is also important to work in a well-ventilated area and to avoid contact with the skin, eyes, and clothing.
If contact does occur, flush the affected area with water for at least 15 minutes and seek medical attention if necessary.
Storage
Cis 1 tert butyl 3 methylcyclohexane should be stored in a cool, dry place away from heat and ignition sources. It should also be stored in a tightly sealed container to prevent evaporation.
Disposal
Cis 1 tert butyl 3 methylcyclohexane should be disposed of in accordance with local regulations. It should not be poured down the drain or disposed of in the trash.
NMR and IR Spectroscopy
Nuclear Magnetic Resonance (NMR) and Infrared (IR) spectroscopy are powerful analytical techniques used to identify and characterize organic compounds. These techniques provide valuable information about the molecular structure, functional groups present, and the dynamic behavior of molecules.
NMR Spectroscopy
NMR spectroscopy relies on the magnetic properties of atomic nuclei, particularly 1H and 13C, to provide detailed information about the molecular structure. The NMR spectrum of cis-1-tert-butyl-3-methylcyclohexane exhibits characteristic peaks that correspond to the different types of hydrogen and carbon atoms in the molecule.
The peaks are assigned based on their chemical shifts, which are influenced by the electronegativity of the neighboring atoms and the molecular environment.The 1H NMR spectrum of cis-1-tert-butyl-3-methylcyclohexane shows a singlet at around 0.9 ppm, which corresponds to the nine equivalent methyl protons of the tert-butyl group.
The protons on the cyclohexane ring give rise to multiplets in the range of 1.0-2.0 ppm, reflecting their different chemical environments. The methyl proton attached to the cyclohexane ring appears as a doublet at around 1.2 ppm due to the coupling with the adjacent methylene protons.The
13C NMR spectrum provides complementary information about the carbon atoms in the molecule. The tert-butyl carbon resonates at around 30 ppm, while the cyclohexane carbons appear in the range of 20-40 ppm. The carbon attached to the methyl group shows a signal at around 35 ppm.
IR Spectroscopy
IR spectroscopy measures the absorption of infrared radiation by a molecule, which corresponds to the vibrational modes of the functional groups. The IR spectrum of cis-1-tert-butyl-3-methylcyclohexane exhibits several characteristic peaks that provide information about the functional groups present.The strong peak at around 2960 cm -1is attributed to the C-H stretching vibrations of the alkyl groups.
The peak at around 1460 cm -1corresponds to the bending vibrations of the C-H bonds in the methylene groups. The absence of a peak in the range of 1620-1680 cm -1indicates the absence of a carbonyl group (C=O).Overall, the NMR and IR spectra of cis-1-tert-butyl-3-methylcyclohexane provide valuable information about the molecular structure and the presence of specific functional groups.
These techniques are essential for the identification and characterization of organic compounds, and they play a crucial role in various fields of chemistry, including organic synthesis, drug discovery, and materials science.
Computational Modeling
Computational methods have been widely employed to investigate the structure and properties of cis 1 tert butyl 3 methylcyclohexane. Molecular dynamics simulations and quantum chemical calculations have provided valuable insights into the molecular behavior and electronic structure of this compound.
Molecular Dynamics Simulations
Molecular dynamics simulations are used to study the dynamic behavior of molecules over time. By simulating the interactions between atoms and molecules, researchers can observe the conformational changes, diffusion, and other dynamic processes that occur in cis 1 tert butyl 3 methylcyclohexane.
These simulations have provided information about the preferred conformations of the molecule, its flexibility, and the energy barriers associated with conformational changes.
Quantum Chemical Calculations
Quantum chemical calculations, such as density functional theory (DFT) and Hartree-Fock (HF) methods, are used to determine the electronic structure and properties of cis 1 tert butyl 3 methylcyclohexane. These calculations provide information about the molecular orbitals, electron density distribution, and various electronic properties such as ionization energy, electron affinity, and polarizability.
By comparing the results of quantum chemical calculations with experimental data, researchers can validate computational models and gain insights into the electronic behavior of the molecule.
FAQ
What are the physical properties of cis 1 tert butyl 3 methylcyclohexane?
Cis 1 tert butyl 3 methylcyclohexane is a colorless liquid with a boiling point of 171-172 °C and a density of 0.86 g/cm³.
How is cis 1 tert butyl 3 methylcyclohexane synthesized?
Cis 1 tert butyl 3 methylcyclohexane can be synthesized via several methods, including the Diels-Alder reaction, the Friedel-Crafts alkylation, and the hydrogenation of tert-butylcyclohexene.
What are the applications of cis 1 tert butyl 3 methylcyclohexane?
Cis 1 tert butyl 3 methylcyclohexane is used as an intermediate in the synthesis of various organic compounds, including fragrances, flavors, and pharmaceuticals. It is also used as a solvent in the paint and coatings industry.
