PLEASE HELP I WILL RATE!!!!!! NEED ANSWERS TO 1,2,3,4,5 ON POST LAB!!!!! THANK YOU

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PLEASE HELP I WILL RATE!!!!!! NEED ANSWERS TO 1,2,3,4,5 ON POST
LAB!!!!! THANK YOU

Please Help I Will Rate Need Answers To 1 2 3 4 5 On Post Lab Thank You 1 (242.76 KiB) Viewed 28 times

Dehydration of Methylcyclohexanol Learning Objectives: · Perform elimination on (or dehydration of )an alcohol to form an alkene ● Employ LeChatelier's Principle to obtain desired product Utilize distillation to selectively remove the desired product to push the reaction to completion Structure analysis will be achieved using proton NMR of your reaction product. ● Introduction In this experiment you will carry out the dehydration of an alcohol. This is a simple yet elegant reaction. The reaction is reversible and the thermodynamics strongly favor the reverse reaction (hydration of cyclohexene). The elegance comes from the simple method, an application of LeChatelier's principle, used to drive the reaction to the right, the desired direction. Because the boiling points of the alcohol are much higher than the alkene, we are able to use the selective fractional distillation of the alkene, the equilibrium is pushed to the right to counteract the effect of the removal of the alkene by distillation. In turn this newly formed alkene is also removed by distillation pushing the equilibrium further to the right producing more cyclohexane which is then again removed by distillation. Thus, using this simple distillation process, the equilibrium can essentially be pushed virtually 100% to the right, despite the natural tendency to strongly favor the reverse reaction. You will carry out the dehydration of either 2-methylcyclohexanol or 4-methylcyclohexanol by heating the alcohol in the presence of phosphoric acid (Figure 1). The yield of this reaction will be increased if the alkenes are removed as they are produced, thus shifting the equilibrium to the right. For this reason, the reaction will be carried out in such a way that the alkene products distill out of the reaction mixture as they are formed. CH3 CH3 OH H₂PO4 or C₂H12 + H₂O methylcyclohexenes A OH Figure 1. Products of this elimination reaction can include (BUT ARE NOT LIMITED TO) the following isomers (Figure 2): CH3 CH3 CH3 4-methyl 1-methyl 3-methyl cyclohexene cyclohexene cyclohexene Figure 2. Elimination reactions such as this can proceed by different mechanisms. Direct elimination (E2) of water from 4-methylcyclohexanol would produce 4-methylcyclohexene, while direct elimination of water from 2- methylcyclohexanol would produce 1- and 3-methylcyclohexene. In the latter instance, the product that is favored by the reaction might be determined by Zaitzev's rule, which states: when HZ is removed from a species to form an alkene, hydrogen is lost preferentially from the carbon atom, of those adjacent to the carbon atom
bonded to Z, that has fewer hydrogens. Thus, if Zaitzev's rule is followed for the dehydration of 2- methylcyclohexanol, then 1-methylcyclohexene would be the favored product. Alternatively, elimination reactions can occur via the formation of a carbocation (E1) and subsequently, rearrangements can take place. This sort of mechanism would result in the formation of 1- and 3-methylcyclohexene, in addition to 4- methylcyclohexene, from the dehydration of 4-methylcyclohexanol. Table 1 lists all of the physical properties of the starting materials and products to help with conversions and identification. Table 1. Physical Properties Compound Mol. Wt. boiling pt. density 2-methylcyclohexanol 114.2 166 0.930 4-methylcyclohexanol 114.2 173 0.914 1-methylcyclohexene 96.2 110 0.813 3-methylcyclohexene 96.2 104 0.801 4-methylcyclohexene 96.2 102 0.799 Precautions: Phosphoric acid (85%) can cause severe burns. Wear gloves and use in the hood. Wash all spills on the skin with cold water for 15 min. Cyclohexanol can be irritating to the respiratory system and skin. Do not breathe vapors and prevent contact with skin. Wear gloves and use in the hood. Distillation apparatus can get quite hot, use care when handling hot glassware. Procedure: Measure 145 mmol of either 2-methylcyclohexanol or 4-methylcyclohexanol in a graduated cylinder. Tare an empty 100 mL round-bottomed flask and cork ring then add the 145 mmol of methylcyclohexanol and record the weight of the liquid. Take the round-bottomed flask back to your hood and add 5 mL of 85% phosphoric acid, drop in a few boiling chips and swirl the flask to mix the reactants. Set up a fractional distillation apparatus using the reaction flask as the boiling flask. Your fractionating column should not contain any packing material. Use a 25 mL graduated cylinder as the receiver and place the cylinder in a beaker full of ice. Boil the reactants gently so that vapors ascend slowly up the column and begin to condense into the receiver. When the vapors reach the still head and the temperature has stabilized, record the still head temperature. Observe it at intervals throughout the reaction. Control the rate of heating so that the distillation rate is 1-2 drops per second or less and the temperature stays below 120°C. Estimate the volume of the alkene (top) layer in the distillate, and as it nears the value you calculated for your theoretical yield, monitor the still head temperature constantly. Lower the mantel and turn it off when you observe a marked temperature change at the still head or foaming and dense white fumes in the reaction flask. Carefully discard the residue in the reaction flask as directed by your instructor. Measure and record the volumes of the alkene and water layers. Wash the distillate in a separatory funnel with two 10-mL portions of saturated sodium bicarbonate solution. Vent frequently! Dry the alkene layer over anhydrous calcium chloride. Filter off the drying agent through a cotton plug in a funnel, and collect the product in a round-bottomed flask. Rinse out your condenser with acetone to remove any water, then purify the product by simple distillation (don't forget to remove the fractional portion of your distillation setup). Collect all the liquid that distills above -2-
Organic Chemistry Laboratory Manual 2020 100°C and below 115°C. Collect the distillate in a tared vial which is kept on ice. Weigh the product. Your lab instructor will prepare and distribute NMR sample with your product. The proton NMR's will be distributed according to your lab instructor's preference. Post Lab Questions: Please include photographs of any hand drawn answers in your electronic notebook (for example: mechanisms and energy diagrams). Draw them out, take photo and insert into the google doc in the post lab question section. 1. Calculate the theoretical volume of water in the distillate. Compare this value and the estimated volume of alkenes which you calculated in the pre-lab assignment with the values that you actually observed. Show your calculations! 2. Draw the mechanism for this reaction that would lead to the products formed for both 2- methylcyclohexanol and 4-methylcyclohexanol. What is the preferred product in each reaction and why? Remember to include the one additional product from 2-methylcyclohexanol that was mentioned in the video. 3. Using the packet of spectra in Moodle, explain how you would evaluate the success of this reaction using proton NMR? (Think about the differences in structure of our three alkenes). 4. Describe the extraction protocol in your own word using the handout in Moodle as your reference. 5. Draw an energy reaction diagram for the conversion of 2-methylcyclohexanol to 1-methylcyclohexene and 3-methylcyclohexene. Please label your axes, AG, Eact, kinetic product, and thermodynamic product. Also, explain why you chose the products to be either kinetic or thermodynamic.
CH3 1 cis-and trans- 2-methylcyclohexanol (unreacted reagent) : 0: НО -OH : 0: sulfuric acid. Flow chart of the distillate work-up -OH CH3 2 1-methylcyclohexene H H 4 Aqueous layer and 5 Aqueous layer 4 and 5 Dry organic products 2, 3, and some of the unreacted 1 5 water wash with 10ml,water Organic layer 2, 3 and some 1 Also traces of 4 and 5 CH3 3 3-methylcyclohexene wash with 10ml, 3N aqueous sodium hydroxide Organic layer 2, 3 some 1 Traces of 5, 4, OH, and Nat Aqueous layer 4, 5, Na and OH™ wash with 10ml, saturated sodium chloride Organic layer 1, 2, 3, and traces of 5 add some anhydrous calcium chloride to remove 5
single_pulse.ex2-25.jdf single pulse 7.0 219 twith X: parts per Million: 1H 5.0 ? 4.0 3.0 2.0 1.0 AJEOL Filename single pulse.ex2-25.j - Delta Author Experiment Sample_id single_pulse.ex2 S#398401 = CHLOROFORM-D Solvent Creation_time Revision_time Current_time 10-MAR-2017 1 10:34:01 10-MAR-2017 11:08:29 = 10-MAR-2017 11:08:44 single pulse - 1D COMPLEX 13107 Comment Data format Dim size Dim_title Dim Dimensiona Site Spectrometer - = 18 = [ppm] - ECX 300 = JNM-ECX300 = 7.0586013 [T] (300 [MHz = 2.90717696 [s] - 1x = 300.52965592 [MHz] = 5(ppm) = 16384 Field strength X_acq_duration x domain x freq x_offset x_points x prescans x_resolution X sweep Irr_domain Irr_freq Irr_offset Tri_domain = 0.34397631 [K] 5.63570784 [x] = 1H = 300.52965592 [MHz] = 5 [pp] = 18 = 300.52965592 [MHz] = 5 [ppm] Tri freq Tri_offset clipped Mod return Scans Total scans = FALSE = 1 = = 8 x 90 width - 10.7 [us] x acq_time Xangle Xatn - 2.90717696 [s] 45 [deg] = 4 [dB] x pule = 5.35 [us] = off =off = off Tri_mode Dante presat = FALSE =1[s] = 30 Initial_wait Recvr_gain Relaxation_delay 51 Repetition time Temp get .06 7.90717825-tel = 460.0[dC1 Marke Jach.
single_pulse.ex2-25.jdf single pulse 1.7 1.6 X: parts per Million : 1H 1.5 158.59 1.4 ON yo? 2 1.3 1.2 wielk 1.0 0.9 1.1 0.8 0.7 AJEOL Filename single pulse.ex2-25.1 Delta = single pulse.ex2 S#398401 Author Experiment Sample i le_id Solvent Creation_time Revision_time Current_time = CHLOROFORM-D - 10-MAR-2017 10:34:01 - 10-MAR-2017 11:09:18 - 10-MAR-2017 11:10:36 = single pulse Comment Data format Dim size Dim title Dim S Dimensions Site Spectrometer = 1D COMPLEX - 13107 18 = [ppm] -ECX 300 - JNM-ECX300 Field strength x acq_duration x_domain xfreq - 7.0586013 [T] (300 [M -2.90717696 [s] = 18 = = 300.52965592 [MHz] X offset = 5(ppm] x points = 16384 X prescans = 0.34397631 [X] = 5.63570784IH=1 = 18 - 300.52965592 [MHz] - 5 [ppm] = 1H X resolution x sweep Irr_domain Irr freq Irr_offset Tri domain Tri_freq Tri_offset clipped Mod_return Scans Total scans - 300.52965592 [MHz] - 5 [ppm] = FALSE = 1 = 8 = 8 = 10.7 [us] = 2.90717696 [s] 45 [deg] = 4 [dB] 5.35 [us] X 90 width X_acq_time X_angle Xatn x_pulse Irr mode Tri mode Dante presat Initial wait Recur_gain Relaxation_delay= 5 [s] - Off = off = FALSE = 1 [s] = 30 Repetition_time = 7.90717696 [s] Temp_get = 460.0[dc] Mark Jsed your ?
single pulse.ex2-25.jdf single pulse 5.7 5.6 X: parts per Million : 1H 5.2 you 5.0 ? 4.5 AJEOL Filename Delta single pulse.ex2-25.j = single pulse.ex2 S#398401 Author Experiment Sample id Solvent Creation_time Revision_time Current_time = CHLOROFORM-D - 10-MAR-2017 10:34:01 = 10-MAR-2017 11:09:18 = 10-MAR-2017 11:11:05 Comment single pulse = 1D COMPLEX = 13107 - 1H - [ppm] = ECX 300 Data format Calze title Dim units Dimensions Site Spectrometer Field strength X_acq_duration x domain x freq X_offset = JNM-ECX300 = 7.0586013 [T] (300 [MHz = 2.90717696 [s] = 300.52965592 [1] = 5 [ppm] =16384 = 1 -0.34397631 [Hz] -5.63570784 [Hz] = 18 x points x prescans X resolution X sweep Irr_domain Irr_freq Irr_offset Tri_domain Tri freq Tri_offset Clipped - 300.52965592 [MHz] = 5[ppm] -18 = 300.52965592 [MHz] • D Mod return Scans Total scans -8 8 = 10.7 [us] = 2.90717696 [s] = 45 [deg) = 4 [dB] x_90_width X_acq_time X angle xatn x_pulse Irr_mode Tri mode Dante presat Initial wait Recvr_gain = 5.35 [us] - Off - off = FALSE = 1 [s] = 30 Relaxation_delay= 5[s] Repetition time Temp_get - 7.90717696 [#] = Mark facole مل
single pulse.ex2-28.jdf single pulse L you? A u 1.1 1.09 1.08 1.07 1.06 1.05 1.04 1.03 1.02 1.01 1.0 0.99 0.98 0.97 0.96 0.95 0.94 0.93 0.92 0.91 0.9 0.89 0.88 0.87 0.86 0.85 0.84 0.83 0.82 X: parts per Million: 1H AJEOL Filename = single pulse.ex2-28.j - Delta Author Experiment Sample id single pulse.ex2 = S#436671 = CHLOROFORM-D Solvent Creation_time = 10-MAR-2017 11:37:45 = 10-MAR-2017 12:12:55 = 10-MAR-2017 12:13:02 Revision time Current time Comment single pulse 1D COMPLEX 13107 Data format Dim_size Dim_title Dim units Dimensions Site Spectrometer = 1H = [ppm] = X = ECX 300 = JNM-ECX300 - 7. (300 (MHz -2.9071769611 = 18 Field strength x_acq_duration X_domain x_freq X_offset x_points prescans - 300.52965592 [M] = 5 [ppm] = 16384 - 1 -0.34397631 [Hz] = 5.63570784 [Hz] X resolution X_sweep Irr_domain Irr freq Irr_offset = 1H = 300.52965592 [MK] - 5 [ppm] - 18 - 300. -5 [2965592 [MHz] Tri domain Tri freq Tri_offset clipped Mod return Scans Total scans = FALSE - 1 -8 = 8 10.7 [ua] - 2.90717696 [s] = 45 [deg) = 4 [dB] x 90 width x_acq_time angle X_atn X pulse Irr mode Tri mode Dante presat Initial wait Recvr_gain - Off - Off = FALSE - 1 [s] = 30 Relaxation_delay Repetition_time 5.50717696 [8] Temp_get = 460.0[d] 5.35 [us] Mark OH you? +?
single pulse.ex2-27.jdf single pulse 1.01 1.0 0.99 0.98 0.97 0.96 0.95 0.94 0.93 0.92 0.91 X: parts per Million: 1H pure ple 0.9 0.89 0.88 0.87 0.86 0.85 0.84 0.83 0.82 0.81 0.8 0.79 AJEOL Filename single pulse.ex2-27.j Del = single pulse.ex2 S#425160 Author Experiment Sample_id Solvent Creation_time Revision_time Current_time = CHLOROFORM-D = 10-MAR-2017 11:18:51 = 10-MAR-2017 11:51:54 = 10-MAR-2017 11:55:57 Comment single pulse - 1D COMPLEX 13107 -1 - 18 Data format Dim_size Dim_title Dim units Dimensions Site Spectrometer [ppm] -ECX 300 -JM-ECX300 -7.0586013 [T] (300 (MHz -2.90717696 [8] -18 = 300.52965592 [MHz] - 5 [ppm] 6384 Field strength X_acq_duration domain x freq X_offset x points Xprescans X resolution x sweep Irr_domain Irr_freq Irr_offset Tri domain Tri_freq Tri_offset clipped Mod return Scans Total scans - 0.34397631 [Hz] = 5.63570784 [Hz] = 1H = 300.52965592 [MHz] - 5 [ppm] - 18 =300.52965592 [MHz] - 5[ppm] - FALSE 8 8 = 10.7 [us] = 2.90717696 [s] - 45 [deg] -4 [43] x 90 width X_acq_time x angle Xatn X pulse ITT mode Tri_mode Dante presat = 5.35 [us] = off - off = FALSE Initial_wait =1[s] = 34 Recur_gain Relaxation_delay= 5[s] Repetition_time = 7.90717696 [=] Temp_get
abundance single_pulse.ex2-27.jdf single_pulse 2.3 2.2 2.1 X: parts per Million: 1H 2.0 1.9 1.8 1.7 1.6 1.5 pure sample 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 AJEOL Filename = single pulse.ex2-27.5 Author = Delta Experiment - single pulse.ex2 S#425160. = CHLOROFORM-D Sample_id Solvent Creation time Revision time Current time = 10-MAR-2017 11:18:51 - 10-MAR-2017 11:51:54 - 10-MAR-2017 11:53:57 Comment single pulse = 1D COMPLEX = 13107 - 18 Data format Din size Din title Dim units Dimensions Site Spectrometer <= (ppm) -ECX 300 = JNM-ECX300 7.0586013 (T) (300 (MHz 2.90717696 [s] = 18 = 300.52965592 (MHz) = 5 [ppm] - 16384 - 1 Field strength x acq_duration X_domain x freq X_offset x points X prescans x_resolution x_sweep Irr_domain Irr_freq Irr_offset Tri domain Tri freq Tri_offset clipped Mod return Scans - 0.34397631 [Hz] = 5.63570784 [kl] = 18 - 300.52965592 [MHz] 5 (ppm) = 18- = 300.52965592 [MHz] = 5 (ppm) TALEZ 1 -8 Total scans x 90 width = 10.7 [us] = 2.90717696 [s] = 45 [deg] - 4 [GB] - 5.35 [us] - Off X_acq_time x_angle x_atn x_pulse Irr_mode Tri mode Dante presat = FALSE Initial wait - 1 [s] Recur gain - 34 Relaxation_delay= 5[s] = off Repetition time = 7.90717696 [s] Temp_get = 460.0fdcl
single_pulse.ex2-27.jdf single pulse 7.0 X: parts per Million : 1H PURE SAMPLE 3.0 AJEOL single pulse.ex2-27.j - Delta single pulse.ex2 Filename Author Experiment Sample id Solvent Creation_time Revision_time Current_time - S#425160 - CHLOROFORM-D - 10-MAR-2017 11:18:51 = 10-MAR-2017 11:51:54 = 10-MAR-2017 11:52:05 = single pulse = 1D COMPLEX = 13107 - 1x Comment Data format Dim_size Dim title Dim_units Dimensions site. Spectrometer - [ppm] - X = ECX 300 - JNM-ECX300 7,0586013[2] (300 [MHz - 2.90717696 [8] Field strength x_acq_duration x_domain x freq X offset 300.52965592 [MHz] - 5[ppm] - 16384 x points 0.34397631 [#] = 5.63570784 [Hz] = 111 = 300.52965592 [MHz] - 5 [ppm] x prescans x_resolution X_sweep Irr domain Irr freq Irr_offset Tri domain Tri_freq Tri_offset clipped Mod_return Scans Total scans - 18 - 300.52965592 [MHz] 5[ppm] - FALSE = 1 <-8 = 8 x 90 width = 10.7 [us] xace time = - 2.90717696 [a] = 45 [deg] - 4 [dB] = 5.35 [us] = off - off x angle X_atn X pulse Irr_mode Tri mode Dante presat Initial wait Recvr_gain Relaxation_delay= 5[s] Repetition time = 7.90717696 [s] Temp get = 460.0 [ac] = FALSE = 1 [s] = 34
abundance 8 single pulse.ex2-26.jdf single pulse 1.04 1.03 1.02 1.01 1.0 X: parts per Million: 1H 0.99 0.98 0.97 0.96 0.95 0.94 0.93 0.92 0.91 0.9 - 2 OH 0.89 0.88 0.87 0.86 0.85 0.84 0.83 0.82 AJEOL single pulse.ex2-26.1 Delta Filename Author Experiment Sample id Solvent Creation_time Revision time Current_time single pulse.ex2 =S#411617 - CHLOROFORM-D - 10-MAR-2017 10:56:02 = 10-MAR-2017 11:29:31 - 10-MAR-2017 11:33:41 single pulse = 1D COMPLEX Comment Data format Din size Dim title Dim units Dimensions = 13107 = 18 = [ppm] = X Site Spectrometer = ECX 300 = JNM-ECX300 Field strength = 7.0586013 [T] (300 [MHz = 2.90717696 [s] = 1H x acq_duration X_domain A X freq x_offset X_points X_prescans = 300.52965592 [MHz] - 5[ppm] =16384 = 1 X resolution = 0.34397631 [Hz] = 5.63570784 [kk] - 18 M .52965592 [MHz] ="5 [ppm] = 18 = 300.52965592 [MHz] = 5 [ppm] = FALSE X sweep Irr domain Irr_freq Irr_offset Tri_domain Tri freq Tri_offset clipped Mod return Scans Total_scans x 90 width Xacq_time x angle X_atn x_pulse Irr mode = 1 = 8 = 10.7 [us] -2.90717696 [s] = 45 [deg] = 4 [dB] = 5.35 [us] - off 721_mode sat = off Dante FALSE = Initial wait =1[8] Recvr_gain = 30 Relaxation_delay= 5 [s] Repetition _time = 7.90717696 [s] Temp get - 460.0 [ac] Kayla Emma 7 OH 300.525
Simulated 1H NMR spectrum of 4- methylcyclohexene CH3 H H H H H H PPM -H -H H FOL
single_pulse.ex2-26.jdf single pulse 2.2 2.1 2.0 X: parts per Million: 1H 1.9 1.8 1.7 1.6 1.5 مجھے OH 1.4 IV 1.3 1.2 1.1 1.0 0.9 0.8 0.7 AJEOL single pulse.ex2-26.j = Delta = single pulse.ex2 Filename Author Experiment Sample id Solvent Creation_time Revision_time Current_time - S#411617 - CHLOROFORM-D - 10-MAR-2017 10:56:02 = 10-MAR-2017 11:29:31 = 10-MAR-2017 11:31:48 single pulse = - 1D COMPLEX - 13107 = 1H Comment Data format Dim size Dim_title Dim units Dimensions Site Spectrometer - [ppm] ECX 300 JNM-ECX300 Field x treg 7. 200023 (300 [MHz = 1H x domain x_freq X_offset x points = 300.52965592 [MHz] = 5(ppm] = 16384 = 1 X resolution x = 0.34397631 [Hz] = 5.63570784 [Hz] ■.1H sweep Irr_domain Irr_freq Ixx_offset Tri_domain at = 300.52965592 [MHz] = 5 (ppm) - 18 300.543 (MHz) = FALSE clipped Mod_return Scans Total_scans = 1 8 8 x 90 width 10.7 [us] = 2.90717696 [s] 45 [deg) 4 [dB] X acq_time X_angle X_atn X pulse Irr_mode Tri mode Dante presat Initial_wait = 5.35 [us] off = off = FALSE = 1 [8] = 30 Recvr_gain Relaxation_delay = 5[s] Repetition_time -7.90717696 [a] - 460.0[4c] Temp_get Карве Египе OK ion
abundance 3- single_pulse.ex2-26.jdf single pulse мил ( 6.0 5.0 X: parts per Million: 1H ON T ~- 4.0 3.0 2.0 AJEOL = single pulse.ex2-26.j - Delta single_pulse.ex2 Filename Author Experiment Sample id Solvent Creation_time Revision_time Current_time =S#411617 = CHLOROFORM-D = 10-MAR-2017 10:56:02 10-MAR-2017 11:29:31 - 10-MAR-2017 11:29:41 single pulse 1D COMPLEX - 13107 = 1H Comment Data format Dim_size Dim_title Dim_units Dimensions site Spectrometer = [ppm] = X = ECX 300 = JNM-ECX300 Field strength 7.0 x_acq_duration 2.90717696 (300 [MHz = 1H X_domain X_freq X_offset = 300.52965592 [MHz] = 5(ppm] x points =16384 x = 1 = 0.34397631 [Hz] X_resolution X_sweep Irr_domain Irr_freq Irr_offset = 5.63570784 [kHz] - 18 = 300.52965592 [MHz] = 5 (ppm) = 18 Tri_domain Tri freq clipped = 300.52965592 [MHz] = 5(ppm) = FALSE - 1 Mod return Scans Total scans 8 - 10.7 [us] = 2.90717696 [s] - 45 [deg) = 4 [dB] x 90 width Xacq_time angle X_atn X pulse Irr_mode Tri mode Dante presat Initial_wait 5.35 [us] - Off = off = FALSE = 1 [8] = 30 Reation_delay= 5[s] Repetition_time = 7.90717696 [s] Temp_get - 460.0 [ac] Kaylo Erna ? Off
Simulated 1H NMR spectrum of 1- methylcyclohexene CH3 H H H H нн PPM H -H H
Simulated 1H NMR spectrum of 3- methylcyclohexene CH3 H OF H H нн PPM H 3 -H -H H ilmu