Oxidation conversion of 4-tert-butylcylcohexanol to 4-tert-butylcyclohexanone dr. peggy kline – chemistry @ smc peggy kline gsa 2016 calendar


• Techniques book: Review the Essays: The Role of the Laboratory (page 1), Learning to do Organic Chemistry (page 41). Intermolecular Forces in Organic Chemistry (page 127), Modern Chromatographic Separations (page 254), and The Spectrometric Revolution (page 309). Specific Techniques: Sections 10.4-10.5 (miniscale extraction), 21.1 (preparing IR samples) 21.6 (IR ATR for solid samples), and 21.7-21.9 (interpreting IR spectra); Chapter 12 (drying organic liquids and recovering reaction products) and Chapter 18 (TLC).

• Techniques (online): The website associated with the Techniques book has videos on the following that you should watch: Handling power kinetic energy of Waste (1.1), Liquid/Liquid Extraction (10.1), Drying of Organic c gastronomie traiteur avis Liquids (11.1), Thin-Layer Chromatography (18.1), and How to Prepare an IR Sample (22.1). This TLC simulator may be helpful as it allows you to explore what happens when solvent polarities are changed. This extraction animation may also be useful.

• Notebook Preparation: Since this is a preparation, or synthesis, lab you must have a reaction equation with structures in your notebook. You need appropriate physical and hazard data for all of the substances used and prepared in the lab. You also need a procedure, as detailed in the Lab Notebooks and Reports Handout. The oxidation and reduction labs are individual experiements and each needs its own title, reference, introduction, reactions, compound/hazard information, and procedure. Eventually you will need to turn in separate lab notebook pages for each experiment individually; therefore, you cannot have any pages that have information for both experiments. The one exception to this electric utility companies in arizona is that it is OK if compounds used in both experiments appear in the compound/hazard information for the oxidation experiment only.

• Instead of the apparatus described in the procedure, we will use a 125-mL Erlenmeyer flask as a reaction vessel. No condenser, Claisen adapter, etc. You may either use a Pasteur pipet to add the sodium hypochlorite solution dropwise over the 15-minute period or you can use a separatory funnel suspended over the Erlenmeyer flask in a clamped iron ring. The latter is more elegant. You still need to use the magnetic stir bar.—try to get one of the ones that are 3-4 cm long. Place the flask directly on the hot plate/stirrer. You don’t need a water bath.

• Bleach oxidation. It might be wise to apply a simple sniff test to the gas in oil briggs and stratton engine bleach solution provided; if it doesn’t smell like bleach, do not use it and notify your instructor as it may have lost its potency. (comment added 3/22/2019). Test the aqueous layer for excess hypochlorite with starch-iodide paper after all of the NaOCl has been added.. You want excess hypochlorite throughout the reaction. You do not want excess hypochlorite after adding the sodium bisulfite. Below is a flowchart for testing for the presence k gas oroville of (excess) NaClO at the end of the reaction. Yes=positive for presence of NaClO. No=negative for presence of NaClO. Go through this process before doing the final reaction TLC.

• TLC Notes and Procedure. Follow this procedure instead of what it says in procedure in “loose-leaf” pages. Please refer to the procedure in the Techniques book for additional experimental details. There will be three lanes: reference ketone, alcohol in reaction mixture before any bleach has been added, and reaction mixture after all bleach has been added. If you really want to do a reference alcohol lane as well, for four total lanes, that is fine as long as the TLC plate is wide enough (t he alcohol reference standard tends electricity sources usa to settle, so make sure that you swirl the bottle before using it).

• Relative Rf values are trans alcohol cis alcohol ketone. The cis and trans isomers show as separate blue spots (sometimes not quite resolved) with an Rf close to 0.85, while the ketone shows an intense maroon spot at or near the solvent front. (Rf values for the developing solvent used are from Dip, I.; Gethers, C.; Rice, T.; Straub, T.S. Journal of Chemical Education 2019, 96, 183-186.

• Reaction mixture at end in lane #3. After all of the bleach has been added and you have completed the electricity lessons 4th grade starch-KI process, including the stirring, but before adding the sodium bisulfite, let the layers separate as directed in the loose-leaf procedure, and spot the organic layer in lane #3, again spotting multiple times. The organic layer is pretty thin and you may have to tilt the flask to see it.

• Visualize the plate using anisaldehyde solution as described in the loose-leaf procedure, including the heating part. Metal-backed TLC plates may be heated directly on the hot plate in a hood without any ether present. Try a setting of about 2.5 to start. We don q gas station’t have enough plate-stirrers for everyone in a full lab section to have two (one for stirring the reaction and one for the TLC heating), so the instructor will probably set up a few hot plates in the hood in Sci 303. You can also heat the plates using a heat lamp, getting the plates as close to the lamp output as possible.

• The visualization can get a bit tricky as there is a fine line between visualizing the 5 gas laws alcohols (which show up less readily than the ketone) and overcooking the plate. Heat the plate until you see the alcohol. Evidence in the literature ( Esselman, B.J. and Hill, N. The Chemical Educator 2018 , 23 , 23-27) indicates that the plate can be visualized simply by placing it in a jar containing a mixture of loose silica gel and iodine, closing the lid, and waiting; however, this did not work well when piloted in February 2019 before the class did the experiment, (Jovany Merham, personal communication, February 2019) so we will not do this.

• If the results from lane #3 of the TLC indicate that alcohol is still present , add 1-2 mL more of bleach solution and stir for 10-15 minutes before gas oil ratio calculator proceding to add the sodium bisulfite. Given that the cis alcohol is more readily oxidized than the trans (see #12 below), you gas approximation may see only one spot for any unreacted (cis) alcohol as opposed to the two spots you should have observed for the alcohol at the beginning of the reaction. Do not do an additional TLC—we’ll assume the reaction is good to go after this.

• At the end of the lab , before you leave, you will turn in the procedure pages with the data added. Don’t forget to include the results of the startch-KI tests and action taken as a result, as well as the result m gasbuddy of the TLC and any action taken as a result. At some point during the lab the instructor will probably check and stamp your procedure pages somewhere. A drawing of the TLC must be in the notebook, along with distances traveled by each substance and the solvent and calculation of Rf values (show work unless you can divide the numbers in your head).

• On the day that the typed portion is due you will turn in any data that you collected during the lab period after the one in which you started the lab (just write it at the top of the first page you turn in that day), calculations (for percent yields and retention factors) in your notebook in a labeled Calculations section, and a drawing of the IR spectrum of your product with an IR summary table, using gas news in hindi the protocol described in the Reporting Spectral Data handout. Also write the mechanism for the reaction, using the structure of one of the two diastereomers for the starting material.

You may use the numbers in front of each of the items below in your report, or the both the numbers and the descriptions. The data should be presented as an ordered (numbered) list. Show the calculation of any items for which you needed a calculator in your notebook in a clearly-labeled Calculations section. Spectra tables go in the notebook, not in the typed portion.

• Describe how the IR spectrum is (or is not) consistent with formation of the expected product and inconsistent with the spectrum of the starting material. In other words, how does the IR show that the reaction has occurred and/or gone to completion, or not if that is the electricity news australia case? If the IR indicates the presence of alcohol and/or water by virtue of having an OH stretch que gases componen el aire, use your final TLC to determine whether or not alcohol appeared to be present at the end of the reaction and what this means for the presence of absence of water/alcohol in the final product.

• Consider the addition of NaHSO 3 solution at the end of the reaction and testing the solution with the starch-KI paper. a. For what substance (alcohol, ketone, NaOCl, NaHSO 3) is the paper testing? b. With what substance does the NaHSO 3 react? c. What would happen to the starch-KI paper to indicate that enough NaHSO 3 had been added? d. What would happen to the starch-KI paper to indicate that more NaHSO 3 needed to be added?