'Synthesis of Acetanilide\r'

'Synthesis of phenylacetamide By: Rick Whitely April 9, 2013 Organic Chemistry research lab 1; Professor J. Hutchison Recrystallization is a frequent manner of purifying organic substances through the differences in solubility at different temperature. In this experiment, acetanilide was produced by acetylation of aniline with acetic anhydride. The crude acetanilide was fade out in a solvent in a heated water bath. The solution was cooled slowly in an ice bath as crystals draw out.As the confused crystallizes from the solution, the limiting reagent phenylamine and the percent yield of 96% was obtained. Introduction: This experiment involves four functional groups common in organic chemistry. The substrate (reactants) which atomic number 18 Aniline and Acetic anhydride are both liquids and one of the results is comforting ( acetanilide). The reaction of aniline with acetic anhydride is a regeneration in which products acetanilide and acetic deadly are obtained. A solid pr oduct (Acetanilide) is obtained so that it whitethorn be recrystallized and a melting point determined.The answer: Aniline (C6H5NH2) + acetic anhydride (C4H6O3) Acetanilide (C8H9NO) + acetic acid (C2H4O2) Results and Discussion: Amines can be treated (acyl groupated, adding a Carbonyl and losing a proton) using Acetic Anhydride as a source of an â€Å"Acyl” group to form an Amide. The Synthesis of Acetanilide (an Amide) through a Nucleophilic Acyl Substitution (addition / elimination) reaction between Aniline (an Amine) is play playing as the Nucleophile and an Acyl group from Acetic Anhydride acting as the Electrophile.The Mechanism: The desired product is spaced from its impurities by differences in solubility. Soluble impurities remain in the cold solvent after recrystallization. The desired product should be as soluble as manageable in hot solvent and as indissoluble as possible in cold solvent. The choice of solvent is therefore critical to the successful recrystal lization which in this experiment, water was used as the solvent because of its solubility. The cypher percent yield was 96%. Procedures: Acetic anhydride (1mL, 10. 8) was added in several small portions along with 6 mL of deionized water to (0. 1 g, 1. 08 m groyne) of aniline. The immediate formation of a solid precipitate was observed. After adding 20mL of deionized water to the mixture, it was indeed heated until all of the material was dissolved. A diaphanous solid was obtained while cooling to room temperature, indeed filtered and washed with 2mL of chilled water. The material was allowed to dry for approximately 15 minutes and (0. 9795 g, 96%) of Acetanilide was recovered. Calculations: Moles of Aniline: 0. 7 g C6H5NH2 / X x 93. 3 g C6H5NH2 / 1 mole = 0. 7g / 93. 13 g x X 93. 13 g / 93. 13 g = X = . 0075 mol x 1000 = 7. 5 mmol Moles of acetic anhydride: 1. 08 g C4H6O3 / X x 102. 09 g / 1 mol = 1. 08 g / 102. 09 g x X 102. 09 g / 102. 09 g = X = 0. 0106 mol 1 mL x 1. 08 g / 1 mL = 1. 08 g Limiting Reagent: 0. 7 g C6H5NH2 x 1 mol C6H5NH2/93. 13 g = 1 mol C8H9NO/ 1 mol C6H5NH2 x 135. 17 g C8H9NO/1 mol C8H9NO = 1. 016 g C8H9NO The limiting reagent is Aniline. Mass of product: .9795 g Acetanilide x 1 mol/135. 17 g Acetanilide = 0. 0073 mol share Yield: Percent yield =\r\n'