'Preparation and Reactivity of Sn1 2-Bromobutane\r'

'Preparation and SN1 Reactivity of 2-Bromobutane Paul DeJong de stopment of Chemistry, Illinois State University, Normal, IL 61790-4160 Submitted: April 4, 2013 Introduction The conclusion of part 1 of the lab is to make believe 2-Bromobutane using SN1 reactions. The purpose of part 2 of the lab is to determine the sex act reactivity of alkyl halides under SN1 conditions. Results and Discussion The overall Reaction The Proposed Mechanism testal Procedure To prepare 2-bromobutane in part one of the lab, you have to destiny up a flask apparatus with a thermowell and a Claisen adapter.Attached to the Claisen adapter is a thermometer measuring the temperature in the flask and a vertical condenser for reflux. add in the reactants to the flask, sulfuric acid, 2-butanol, and ammonium cliche. Heat to 95OC and indeed maintain temperature for 30 minutes. Then, water was added and simple distillment began. The aqueous layer of the distillate was removed leave the product, 2-bromobu tane. For part 2, two drops of distributively of the following were situated in 3 different test tubes: 2-bromobutane, 1-bromoutane and 2-bromo-2-methylpropane.In each of the tubes an even amount of silver nitrate is added. Observations of the reactions precipitate are recorded. Same process is done with 2-chlorobutane, 2-iodobutane, and 2-bromobutane. Experimental Stoichiometry mixed| Molecularweight| Quantity| Moles| 2-butanol| 74. 12 g| 7. 4 mL (6. 0 g)| 0. 081| Sulfuric acid| 98. 08 g| 20 mL (12M)| 0. 24| Ammonium bromide| 97. 94 g| 8. 0 g| 0. 082| The contain reactant is 2-butanol. hand Data 2-bromobutane| | Molecular Weight| 137. 02 g|Theoretical Yield (moles)| 0. 081 mol| Theoretical Yield (grams)| 11. 10 g| Actual Yield| 10. 11 g| NMR Table Signal| chemical substance Shift| Multiplicity| Integration| A| 4. 11| Multiplet| 1H| B| 1. 85| Pentet| 2H| C| 1. 60| Doublet| 3H| D| 1. 08| Triplet| 3H| Reactivity of Alkyl Halides Compound| Observations at Room Temp| Observations upon Heating| 1-bromobutane| put down| in truth little change but some fresh ppt| 2-bromobutane| Clear| more or less cloudy white ppt| 2-bromo-2-methylpropane| cooked tint| Very milky white ppt|Compound| Observations at Room temp| Observations upon heating| 2-chlorobutane| Clear| No ppt at all| 2-bromobutane| Clear| Moderately white and some yellow ppt| 2-iodobutane| Dark brown| Thick, milky white and yellow ppt| Conclusion Overall, the introductory part of the lab produced 2-bromobutane using SN1 reactions. This product was whence used in the second part of the experiment to determine the relative reactivities of alkyl halides. Reactivity increases as follows 1O < 2O < 3O and Cl- < Br- < I â€\r\n'