Time as a Determinate of Final Product in a Dehydration Reaction
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.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 Zaitzev's rule (Lehman). This should be due to the fact that the cis isomer has 2 anti-coplanar hydrogens. T
6 in every fraction's spectra indicating the presence of methylenecyclohexane. 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. In the spectra for fraction one a 3:1 ratio of trans to cis was observed. 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. , California: Brooks/Cole Publishing, 1996. 79 will decrease as well as the peak for 1-methylcyclohexene due to termination of that products formation. 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. , Operational Organic Chemistry, 3rd ed. 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. 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.
Common topics in this essay:
Standish NMR,
Effect Clausen,
Evelyn Effect,
Discussion NMR,
CDCL3 NMR,
Alaska Abstract,
Organic Chemistry,
GC Figure,
cis isomer,
CH2CL2 NMR,
cis trans,
trans isomers,
cis trans isomers,
Fairbanks March,
third fraction,
spectra fraction,
organic chemistry,
starting material,
cis isomer 2-methylcyclohexanol,
form 1-ethylcyclopentene,
fraction cis,
trans isomer,
fraction cis isomer,
spectra third fraction,
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