Preparation of 1-Bromobutane and Reactivity of Alkyl Halides
Experiment 1: Preparation of 1-Bromobutane and Reactivity of Alkyl Halides
Objective: The purpose of this lab is to prepare 1-bromobutane from 1-butanol in an acid-catalyzed substitution reaction. While the reaction would be expected to occur as SN2 due to the primary nature of the substrate, because H2SO4 is used as a solvent, the conditions are very polar and the reaction can proceed via an SN1 reaction. The main objective is to obtain test results to determine the mechanism of the reaction and purity of the product.
Introduction: The techniques used in this laboratory included reflux, distillation, and extraction as well as obtaining IR and NMR spectroscopy. The reaction of 1-Butanol to 1-Bromobutane occurs via a substitution reaction. This reaction type can proceed via either the SN1 or SN2 mechanisms. SN2 reactions have a second order rate and proceed in a single step (ie. The leaving group leaves and nucleophile attacks all in one step) and leads to inversion of configuration. In contrast, an SN1 reaction occurs at a first order rate and proceeds in two steps between which an intermediate carbocation is formed. In this reaction type there is both inversion and retention of configuration. Analysis will be done to determine by which mechanism the reaction proceeds. To catalyze the substitution reaction, Reflux is employed. Reflux is a technique that involves the evaporation of liquid, condensation of vapors, and the return of these condensed vapors to the reaction vessel by condensation on the cool glass. Reflux is used in this experiment to catalyze the chemical reaction from 1-Butanol to 1-Bromobutane because it allows the reaction to be heated for a long period of time without losing the volatile reactants or products. Similar instruments are used for the distillation method, which allows the separation of two liquids based on their boiling points. The more volatile components (which have a higher vapor pressure and lower boiling point) will be
Objective: The purpose of this lab is to prepare 1-bromobutane from 1-butanol in an acid-catalyzed substitution reaction. While the reaction would be expected to occur as SN2 due to the primary nature of the substrate, because H2SO4 is used as a solvent, the conditions are very polar and the reaction can proceed via an SN1 reaction. The main objective is to obtain test results to determine the mechanism of the reaction and purity of the product.
Introduction: The techniques used in this laboratory included reflux, distillation, and extraction as well as obtaining IR and NMR spectroscopy. The reaction of 1-Butanol to 1-Bromobutane occurs via a substitution reaction. This reaction type can proceed via either the SN1 or SN2 mechanisms. SN2 reactions have a second order rate and proceed in a single step (ie. The leaving group leaves and nucleophile attacks all in one step) and leads to inversion of configuration. In contrast, an SN1 reaction occurs at a first order rate and proceeds in two steps between which an intermediate carbocation is formed. In this reaction type there is both inversion and retention of configuration. Analysis will be done to determine by which mechanism the reaction proceeds. To catalyze the substitution reaction, Reflux is employed. Reflux is a technique that involves the evaporation of liquid, condensation of vapors, and the return of these condensed vapors to the reaction vessel by condensation on the cool glass. Reflux is used in this experiment to catalyze the chemical reaction from 1-Butanol to 1-Bromobutane because it allows the reaction to be heated for a long period of time without losing the volatile reactants or products. Similar instruments are used for the distillation method, which allows the separation of two liquids based on their boiling points. The more volatile components (which have a higher vapor pressure and lower boiling point) will be