Synthesis of an Alkyl Halide
ASynthesis of an alkyl halide
Jade A. Chuahiong and Marika Bianca F. Morioka
Institute of Chemistry, University of the Philippines, Diliman, Quezon City 1101 Philippines
Date Performed: April 25, 2013; Date Submitted: April 30, 2013
Alkyl halides could be synthesized through several processes and using different compounds as reactants. One of the simplest method used is the addition of a hydrogen halide to an alcohol. In this research, tert-butyl alcohol was reacted with cold concentrated HCl to produce tert-butyl chloride. The crude product was distilled to yield a pure tert-butyl chloride. The tert-butyl alcohol, together with HCl, underwent an SN1 nucleophilic substitution reaction, which is composed of three steps—(1) propanation of alcoholic oxygen, (2) formation of carbocation, and (3) attacking of the nucleophile to the carbocation. The experiment was only able to yield 0.504 grams or 5.21% of the theoretical yield of 9.679 grams, which is considered as extremely low percent yield. This result could have resulted from various experiment and experimenter errors and other uncontrollable environmental factors.
Introduction
An alkyl halide or haloalkane is composed of hydrocarbons with a halogen attached to a sp3-hybridized carbon. It resembles an alkane with a halogen attached to it. Halogens are fluorine, chlorine, bromine, and iodine. Any of these halogens seen to be attached to an alkane, could then be identified as alkyl halides. They are generally polar because of the electronegativity difference of carbon (2.5) with the halogen (2.5-4.0). However, most alkyl halides are found to have low solubility in water. They are miscible with each other and with other non-polar solvents as well. The infamous chlorofluorocarbons (CFCs) that are active destroyers of the ozone layer are probably the most common example of alkyl halides. Common alkyl halides used in the laboratory are dichloromethane or methylene chloride (CH2Cl2), trichloromethane or
Jade A. Chuahiong and Marika Bianca F. Morioka
Institute of Chemistry, University of the Philippines, Diliman, Quezon City 1101 Philippines
Date Performed: April 25, 2013; Date Submitted: April 30, 2013
Alkyl halides could be synthesized through several processes and using different compounds as reactants. One of the simplest method used is the addition of a hydrogen halide to an alcohol. In this research, tert-butyl alcohol was reacted with cold concentrated HCl to produce tert-butyl chloride. The crude product was distilled to yield a pure tert-butyl chloride. The tert-butyl alcohol, together with HCl, underwent an SN1 nucleophilic substitution reaction, which is composed of three steps—(1) propanation of alcoholic oxygen, (2) formation of carbocation, and (3) attacking of the nucleophile to the carbocation. The experiment was only able to yield 0.504 grams or 5.21% of the theoretical yield of 9.679 grams, which is considered as extremely low percent yield. This result could have resulted from various experiment and experimenter errors and other uncontrollable environmental factors.
Introduction
An alkyl halide or haloalkane is composed of hydrocarbons with a halogen attached to a sp3-hybridized carbon. It resembles an alkane with a halogen attached to it. Halogens are fluorine, chlorine, bromine, and iodine. Any of these halogens seen to be attached to an alkane, could then be identified as alkyl halides. They are generally polar because of the electronegativity difference of carbon (2.5) with the halogen (2.5-4.0). However, most alkyl halides are found to have low solubility in water. They are miscible with each other and with other non-polar solvents as well. The infamous chlorofluorocarbons (CFCs) that are active destroyers of the ozone layer are probably the most common example of alkyl halides. Common alkyl halides used in the laboratory are dichloromethane or methylene chloride (CH2Cl2), trichloromethane or
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