Time As A Determinate Of Final Product In A Dehydration Reaction Essay Example For Students

Time As A Determinate Of Final Product In A Dehydration Reaction Essay Time as a Determinate of Final Product in a Dehydration ReactionRobert Simack, Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, Alaska. Abstract: This study involved acid dehydration of 2-methylcyclohexanol. The results varied depending on the time elapsed after initial reaction. I attempted to prove the Evelyn Effect, which stated that over a period of time the products of the aforementioned reaction will beobserved to change volume so that those products formed by a cis isomer of 2-methylcyclohexanol will form first. However, once all molecules in the cis isomer undergo reaction the remaining trans configured 2-methylcyclohexanols will proliferate during the latter period of the reaction. I also postulated as to the possible formulation of 1-ethylcyclopentene, and to the cause of such an event. We will write a custom essay on Time As A Determinate Of Final Product In A Dehydration Reaction specifically for you for only $16.38 $13.9/page Order now Introduction: After researching acid-catalyzed dehydration reactions (McMurray) and background on the Evelyn Effect (Clausen) I hypothesize that the cis isomer of 2-methylcyclohexanol will react via an E1 type process forming 1-methylcyclohexene according to predictions from Zaitzevs rule (Lehman). This should be due to the fact that the cis isomer has 2 anti-coplanar hydrogens. These two hydrogens should make the molecule more reactive. The trans isomer, with only one anti-coplanar hydrogen, should be slower to react and will form a 3-methylcyclohexene. In addition the 1-ethylcyclopentene will be formed from both the cis and trans isomers but only if the hydroxyl group is in an equatorial position. In that position electrons from the ring may attack the alcohol directly from behind pushing it off the ring and forming a five-membered ring instead. Results ; Discussion: An NMR (300MHz) spectra of the original reagent and the three fractions provided a huge amount of information in support of my hypothesis. Both cis and trans isomers were present in the spectra for the original material as well as for the first two fractions. The alcohols hydrogen showed up at approximately 3.79 and 3.1 for cis and trans respectively. In the spectra for pure starting material (ref: Jim Starr /Steve Standish NMR 24 March, 2000) cis isomers of starting material comprised only 25% of the sample compared to 75% of trans as observed in the integration of peaks. In the spectra for fraction one a 3:1 ratio of trans to cis was observed. In the spectra of fraction two the cis isomer nearly disappeared; the ratio was roughly 6:1 trans/cis. Finally, in the spectra of the third fraction the cis isomer was absolutely imperceptible while the integration of trans was nearly twice that of the integration from fraction one. These spectra show that cis reacted fi rst and was quickly consumed by the reaction leaving trans isomers to finish the reaction. Because it is known that the reaction with cis starting material caused both 3-methylcyclohexene and 1-methylcyclohexene I postulated that the foremost product of the latter stages of the reaction must be 3-methylcyclohexene, which is the sole product of the trans reaction (McMurray, chap. 11.12). In addition to the cis and trans peaks the peaks for both 3-methylcyclohexene and 1-methylcyclohexene could be found on the spectra at 5.7 and 5.4 respectively. The NMR showed that the integration of 1-methylcyclohexene dropped only slightly throughout the reaction while the integration of 3-methylcyclohexene increased nearly tenfold. The findings from the spectra prove the hypothesis that the cis reaction will go the fastest followed by the trans because as the cis is consumed its peak at 3.79 will decrease as well as the peak for 1-methylcyclohexene due to termination of that products formation. Also, peaks for 1-ethylcyclopentene begin to show in the spectra for the second fraction and increase in size (area beneath the peak) by the spectra of the third fraction. At the root of this phenomena is steric hinderance. Both the cis and trans isomers will form 1-ethylcyclopentene (fig. 1). However, because of steric hinderance the trans isomer is favored to form the 1-ethylcyclopentene. This fact will explain why more of the pentene shows up in the third fraction. .ucb0d8b367cbe537fb5a26519d8487950 , .ucb0d8b367cbe537fb5a26519d8487950 .postImageUrl , .ucb0d8b367cbe537fb5a26519d8487950 .centered-text-area { min-height: 80px; position: relative; } .ucb0d8b367cbe537fb5a26519d8487950 , .ucb0d8b367cbe537fb5a26519d8487950:hover , .ucb0d8b367cbe537fb5a26519d8487950:visited , .ucb0d8b367cbe537fb5a26519d8487950:active { border:0!important; } .ucb0d8b367cbe537fb5a26519d8487950 .clearfix:after { content: ""; display: table; clear: both; } .ucb0d8b367cbe537fb5a26519d8487950 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .ucb0d8b367cbe537fb5a26519d8487950:active , .ucb0d8b367cbe537fb5a26519d8487950:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .ucb0d8b367cbe537fb5a26519d8487950 .centered-text-area { width: 100%; position: relative ; } .ucb0d8b367cbe537fb5a26519d8487950 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .ucb0d8b367cbe537fb5a26519d8487950 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .ucb0d8b367cbe537fb5a26519d8487950 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .ucb0d8b367cbe537fb5a26519d8487950:hover .ctaButton { background-color: #34495E!important; } .ucb0d8b367cbe537fb5a26519d8487950 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .ucb0d8b367cbe537fb5a26519d8487950 .ucb0d8b367cbe537fb5a26519d8487950-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .ucb0d8b367cbe537fb5a26519d8487950:after { content: ""; display: block; clear: both; } READ: Coordinate WSH Management System with Legal Compliance EssayFinally, a tiny peak showed at 4.6 in every fractions spectra indicating the presence of methylenecyclohexane. This product formed from the original product by acid catalyst. Experimental: An apparatus was constructed with a round bottom flask topped by a claisen adaptor in which was placed a thermometer and a condensing tube. In the apparatus 150mmole of 2-methylcyclohexanol was mixed with 5mL H3PO4 and distilled. The distilled liquid was collected in three tubes, at approximately 4mL per tube, labeled fraction 1, 2 and 3. Each fraction was placed in a centrifuge tube and combined with 4mL saturated NaHCO3. The aqueous layer was removed and MgSO4 was added for a final separation. The solid and aqueous layers were then removed and the final product was combined with CDCL3 in an NMR tube in preparation for spectra. The liquid remaining in the original apparatus was put through the separation process described above. However, instead of CDCL3 as a spectrum reagent we used CH2CL2. Also, an NMR was not performed on the remaining liquid but instead a GC. Figure 1: Reactions of cis and trans isomers of 2-methylcyclohexanol during acid-catalyzed dehydration. BibliographyClausen, Tom, ?Organic Chemistry 324 Lecture,? Univeristy of Alaska, Fairbanks, March 20, 2000. Lehman, John W., Operational Organic Chemistry, 3rd ed., New Jersey: Prentice-Hall, Inc., 1999. McMurry, John, Organic Chemistry, 4th ed., California: Brooks/Cole Publishing, 1996. Science Essays

War and The Holocaust essays

War and The Holocaust essays As the old saying goes, there are always two sides to every story. This rings true for war and the Holocaust. There were individuals who were in support of war, albeit their knowledge of its destructive powers, and there were some people who saw its disadvantages through their own eyes, and were therefore vehemently against it. One side saw war and the Holocaust as a positive step towards progress and development, while another side saw unjust destruction and death. Both Bernhardi and Mussolini saw benefits of war for European culture, but Remarque, Monks and Graebe saw, through their own actual experiences, that the benefits acquired through war did not outweigh the disadvantages that it unleashed. In his essay, General Friedrich Von Bernhardi defended the act of war, saying that humankind cannot escape it. He says that, ...the struggle between nations is inevitable... (Bernhardi 177). Furthermore, he says that the development of a country could be, for the most part, attributed to battle. Bernhardi mentions that although war has its setbacks, it is also a creative and purifying power (Bernhardi 177), and a life-giving principle (Bernhardi 178). In addition, Bernhardi admits that war temporarily disturbs industrial life, interrupts quiet economic development...and emphasizes the primitive brutality of man. (Bernhardi 177), but says that war is a need that man has to heed, a biological necessity of the first importance (Bernhardi 177) that cannot be taken away from society. He further upholds his argument by defining the search for peace and the abolishment of war as a journey for the weak and cowardly. According to Bernhardi, ...this desire for peace has rendered most civiliz ed nations anaemic... (Bernhardi 177). Moreover, Bernhardi argues that war has greater benefits. According to Bernhardi, war will furnish...a nation with favourable vital conditions.....