Preparation of 2 chloro 2 methylpropane. GB1559447A 2022-10-28
Preparation of 2 chloro 2 methylpropane Rating:
2-chloro-2-methylpropane, also known as isobutyl chloride, is a halogenated hydrocarbon with the chemical formula C4H9Cl. It is a colorless liquid with a sweet, fruity odor and is commonly used as a solvent and as a starting material for the synthesis of various chemicals.
There are several methods for preparing 2-chloro-2-methylpropane, but one common method involves the reaction of isobutanol with hydrochloric acid and phosphorus pentachloride. The reaction can be represented by the following equation:
C4H10O + HCl + PCl5 → C4H9Cl + HPOCl3
In this reaction, isobutanol is treated with hydrochloric acid and phosphorus pentachloride to form 2-chloro-2-methylpropane and phosphorus oxychloride as byproducts. The reaction is typically carried out in a solvent such as dichloromethane or ether, and it can be heated to accelerate the reaction.
Another method for preparing 2-chloro-2-methylpropane involves the reaction of isobutylene with hydrochloric acid and a catalyst such as zinc chloride. The reaction can be represented by the following equation:
C4H8 + HCl + ZnCl2 → C4H9Cl + ZnCl
In this reaction, isobutylene is treated with hydrochloric acid and zinc chloride to form 2-chloro-2-methylpropane and zinc chloride as a byproduct. The reaction is typically carried out at a temperature of around 50-60°C and can be stopped when the desired yield of 2-chloro-2-methylpropane is reached.
Regardless of the method used, it is important to follow proper safety precautions when handling 2-chloro-2-methylpropane, as it is flammable and can be toxic if inhaled or ingested. It is also important to properly dispose of any waste generated during the synthesis of 2-chloro-2-methylpropane to prevent environmental contamination.
In summary, 2-chloro-2-methylpropane can be prepared through the reaction of isobutanol with hydrochloric acid and phosphorus pentachloride or through the reaction of isobutylene with hydrochloric acid and a catalyst such as zinc chloride. It is important to follow proper safety precautions when handling and synthesizing 2-chloro-2-methylpropane and to properly dispose of any waste generated.
If you get any on your person, thoroughly wash the affected area with water. The OH group is being substituted by a chlorine ion. Science Home Bulletins Courses Equipment All Equipment Buy It Guides Make It Guides Guides HazCards Laboratory Handbook Join CLEAPSS Membership Documents Mailing List Practical Procedures All Procedures Biology Chemistry Physics Recipe Sheets Student Safety Sheets Subject Areas All Subjects Biology Chemistry Physics Supplementary RAs Teaching Resources Technicians Technicians Home Job Adverts Technicians Networks Buy It Guides Make It Guides Technician Tips Useful Links What's New Videos. Extracts from this document. Wear gloves and avoid all contact with skin, eyes, and clothing. Concentrated hydrochloric acid is very corrosive and there are HCl fumes above the concentrated HCl solution, so we should wear safety spectacles during the whole experiment and transfer of acid should be done in fume cupboard. This is important because the cyclohexene formed may react with water to form back cyclohexanol.
Nucleophilic Substitution Reactions of Alkyl Halides
The tert-butyl chloride product was then washed with distilled water 8 mL , shaken and the pressure was released. It is based on a pure liquid having a narrowly defined boiling point, which needs, of course, to be different from the boiling points of other components present in the mixture. We were only using a measuring cylinder to measure each reagent, which was not quite accurate. In this experiment, there are eleven small reaction tubes and will contain each of the following halides 1-Chlorobutane, 1-Bromobutane, 2-Chlorobutane, 2-Cholor-2- methylpropane, bromobenzene, 1-Chloro-2methlypropane, 2-bromobutane, and 2-bromo-2- methylpropane. R groups CH3 in this experiment Conclusion 3. These are easily made from materials like alcohol, alkenes, etc. Structure of the reactant 3o carbon increases the stability of the carbonium ion formed in the intermediate.
Preparation of haloalkane. The purpose of this experiment is to prepare 2
The separating funnel was then clamped and left to sit while the layers separated completely. With the SN1 pathway, a carbonium ion is formed as an intermediate. This reaction takes place at room temperature as methylpropan-2-ol is a tertiary alcohol which undergoes substitution very readily. Abstract This laboratory experiment aimed to obtain 2-chloro-2-methylpropane by SN1 reaction, so the objective was to perform a boiling point test to check whether the obtained product is right or not. One thing to mention is that the protic solvent was used in order to increase the nucleophilicity.
In the SN2 reactions, the molecules react the fastest is ones that can form carbocations to have a more stable compound, the tertiary structes are favored in this reaction. Once the initial reaction ceased, a stopper was placed on the separating funnel, and the mixture was shaken vigorously for about 15 minutes. The pressure was released frequently, during the time frame for which it was shaken. Distillation of cyclohexene from the reaction mixture when it was formed. Reactants are tert-butanol and concentrated hydrochloric acid. Aqueous sodium bicarbonate solutions can be irritants upon evaporation. The product was decanted through a funnel into a dry round bottom flask, to which 4 boiling chips were added.
This might contributed quite a lot on the error in this experiment. We also figured that the molecules with the bromine atom would react faster than the chlorine since bromine is a better leaving group. They are also flammable. Purification process includes removal of acid, dehydration and distillation. There were many cavities which diffracts lights, so a slightly different colour may be observed.
If you get any on your person, thoroughly wash the affected area with water. Wear gloves, and avoid all contact with skin, eyes, and clothing. In a test tube of cold acidified potassium manganate VII , a type of oxidizing agent with cyclohexene, cyclohexa-1,2-diol is formed with the disappearance of purple colour of the acidified potassium manganate VII. They serve as the building blocks for the synthesis of numerous new functional groups. Experimental: See attachment Results: Reaction Time in Sodium Iodide in Acetone Solution SN2 Reaction Observed Room Temperature 50 °C Group 1: 1-bromobutane Yellow, cloudy 24 seconds 2-bromobutane Clear, Cloudy - 1 minute 2-bromo-2- Yellow coloring - 23 seconds methylpropane Bromobenzene Yellow coloring - 30seconds Group 2: 1-cholorbutane Clear cloudiness - 1:18 seconds 2-chloro-2- methylpropane Yellow coloring No reaction No reaction 1-chloro-2- methylpropane Yellow coloring No reaction No reaction Group 3: 1-bromobutane Yellow, cloudy 25seconds - 2-bromobutane Clear, cloudy - 18 seconds 1-chlorobutane Clear, cloudy 5 seconds - 2-chlorobutane No reaction No reactions Reaction Time in Ethanolic Silver Nitrate in Acetone Solution SN1 Reaction Observed Room Temperature 50 °C Group 1: 1-bromobutane Pale yellow, cloudiness 8 seconds 2-bromobutane Clear cloudy 10 seconds 2-bromo-2- methylpropane Yellow cloudy and small crystals 4 seconds Bromobenzene Clear cloudy 1 second Group 2: 1-cholorbutane Cloudy with crystals 3 seconds 2-chloro-2- methylpropane Pale yellow, cloudy 2 seconds 1-chloro-2- methylpropane Cloudy with crystals 4 seconds Group 3: 1-bromobutane Yellow, cloudy 6 seconds 2-bromobutane Yellow, cloudy 4 seconds 1-chlorobutane Yellow, cloudy 4 seconds 2-chlorobutane Yellow, cloudy 9 seconds Reaction time with 2-cholorbutant in two different solutions Observations RT 50 °C 1% ethanolic silver nitrate Yellow, cloudy, crystals 9 seconds 1% silver nitrate mixture of 50% ethanol and 50% water Yellow, cloudy, crystals 1: cholorbutane reacted the slowest as a secondary.
Another reason could be that in the separating funnel, the mixture may not have been able to completely react which means that there are impurities still present in the product. Since we are testing 2- chlorobutane the more polar the solvent the more the SN2 reaction is favored. In the last part we tested 2-chlorobutane in 1% ethanolic silver nitrate solution and 1% silver nitrate in a mixture of 50% ethanol and 50% of water. Safety and Hazards 2-methyl-2-propanol and 2-chloro-2-methylpropane are volatile, irritants and are toxic if ingested. The aim of this experiment was mainly to prepare 2-chloro-2- methylpropane, and purify it using distillation techniques. In this experiment, we used water as a solvent which is of a high polarity, so this increases the rate of substitution.
Another reason is that while running off the lower layers from the separating funnel, a little bit could still have been left in the separating funnel as it is hard to get rid of the exact accurate amount, leading to contamination of the mixture. Guard tube containing soda lime 14. Preparation of the liquids was required before distillation could occur. The syntheses are frequently carried out through nucleophilic substitution reactions, in which the halide is substituted with another group, such as cyano, hydroxyl, etc. The 1% ethanolic silver nitrate solution should react faster than ethanol and water because it is mor polar. Introduction Among organic chemists, SN1 reaction is widely known as dissociative mechanism.