Preparation of Identification by Ir and Nmr Spectroscopy Essay

The reactive acid chloride can then be treated with a primary or secondary amine to give the amide along with HCl, which reacts with the inordinateness amine to give an alkylammonium chloride salt. The mechanism of this process is shown on the following summon in Scheme 22 pic Scheme 2 To carry prohibited this response, the apparatus shown in intent 1 will be assembled. The apparatus must be dry, since thionyl chloride will react with water to give due south dioxide and hydrogen chloride.The acid chloride will then be cooled to agency temperature and fade out in anhydrous ether. Ice-cold diethylamine will be added as a solution in anhydrous ether to form the amide. The resulting ether miscellanea will washed with aqueous sodium hydrated oxide (to remove whatsoever excess acid chloride), then washed with hydrochloric acid (to remove each excess diethylamine).The resulting ether solution of DEET will be dried and evaporated to pay the crude product, which will then be pur ified by column chromatography to relent pure DEET. The percent yield from m-toluic acid will be mulish and the product will be analyzed by transmission infr ared light spectroscopy (IR) as a neat smack using NaCl plates5 to plump for its structure by (1) looking at the major absorptions and comparing them to a correlation table6 and (2) by comparing the spectrum to that of an authentic sample.Thionyl chloride is toxic and corrosive Do not breath the vapors Use in a roof When heating a reply apparatus, be sure that it is open to the course so that pressure build up and subsequent rupture of the apparatus does not occur. When heating liquids, make sure the liquid is stirred (or a boiling chip is added) to pre beam bumping. When performing an extraction, make sure to vent the separatory funnel often to prevent pressure build-up. The apparatus shown in omen 1 was assembled.The 10-mL reaction flask was charged with 0. 275 g of m-toluic acid (0. 0020 mol) and 0. 30 mL of thionyl chloride (0. 492 g, 0. 0041 mol). The condenser water was started, and the mixture was gently heated with breathing in on an aluminum block (block temp 90 oC) until boiling started. The reaction mixture was then gently boiled for almost 15 numbers. subsequently the boiling period was finished, the reaction mixture was cooled to room temperature. 4. 0 mL of anhydrous ether were added, and the mixture was stirred at room temperature until a homogeneous mixture was obtained. To this solution was added (dropwise over a 15 minute period) a solution of 0. 6 mL of cold (0 oC) diethylamine (0. 462 g, 0. 0063 mol) in 1. 33 mL of anhydrous ether. During the addition, a thick white cloud of diethylamine hydrochloride was formed. aft(prenominal) complete addition, the reaction mixture was stirred at room temperature for about 10 minutes. 10% aqueous sodium hydroxide (2 mL) was then added, and the reaction mixture was stirred for an additional 15 minutes at room temperature, then poured in to a separatory funnel and allowed to separate. The aqueous mold was discarded, and the organic class was washed with an additional portion of 10% aqueous sodium hydroxide (2 mL), followed by a portion of 10% hydrochloric acid (2 mL).The organic layer was washed with water (2 mL), dried (Na2SO4) and evaporated to yield crude N,N-diethyl-m-toluamide as Acheronian brown liquid. The crude product was filtered through a short aluminum oxide column using hexane as the eluent ( 5 mL). The hexane solution was evaporated to give 0. 340 g of pure N,N-diethyl-m-toluamide as a yellow liquid. Reaction of m-toluic acid with thionyl chloride, followed by diethylamine produced 0. 340 g of a yellow liquid the IR spectrum of which unequivocally showed the posture of the amide carbonyl functional group at 1633 cm-1. In addition, absorptions due to acyclic C-H (2980 2880 cm-1), and aromatic C=C (at 1585 cm-1). The IR spectrum is attached to this report.These data are consistent with the structur e of N,N-diethyl-m-toluamide (DEET), shown in Figure 2 below pic Figure 2 N,N-Diethyl-m-toluamide (DEET) In addition, the IR of the product closely corresponds with that of an authentic sample of N,N-diethyl-m-toluamide (DEET) shown in the lab text. 9 Also, the 1H-NMR shows the heraldic bearing of four (4) aromatic protons in the region 7. 3 7. 1 ppm, as well as a three (3) proton singlet at 2. 35 ppm, which corresponds to the benzylic methyl group. The presence of two ethyl groups is clearly shown by the presence of two quartets which incorporate to 2 protons each at 3. 53 and 3. 24 ppm, and two triplets which desegregate to 3 protons each at 1. 23 and 1. 09 ppm.