3 cis 2 butene and trans 2 butene could easily be

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3) Cis-2-butene and trans-2-butene could easily be differentiated using proton NMR by obtaining a spectrum and calculating the coupling constants. This could be accomplished by identifying the chemical shifts of the vinylic hydrogens in ppm, calculating the difference, and then multiplying the difference by the spectrometer frequency in Hz. If this value falls in the range of 6-14 Hz (typically 10 Hz), then the structure is Z isomer. If the value falls in the range of 11-18 Hz (typically 16 Hz), then the structure is the E isomer.
4) The synthesis of methyl 4-methoxycinnamate adhered to the first principle of Green Chemistry in that it prevented excess waste from being created. This was accomplished because the HWS reaction is stereoselective, thus only one isomer (the E isomer in this case) was formed, which prevents excess waste from being created in the form of the other stereoisomer. Additionally, principle five is adhered to because safe solvents and auxiliaries were used. By preparing a phosphonate ylide, the subsequent phosphate ester byproduct is soluble in water and did not introduce danger during separation or disposal. Lastly, principle nine was followed in the sense that a catalytic reagent was used in lieu of a stoichiometric reagent. Since potassium carbonate was utilized as a catalyst, there was no need to introduce an additional reagent that would have been consumed during the course of the reaction. Literature Cited 1) Cheung, L. L. W.; Lin, R. J.; McIntee, J. W.; Dicks, A. P. Chemical Educator 2005, 10 (4), 300–302. 2) SDBSWeb : (National Institute of Advanced Industrial Science and Technology, March 1, 2015) 3) K, S. (accessed Feb 22, 2018) 4) Stabile, R. G.; Dicks, A. P. J. Chem. Educ., 2004, 81, 1488-1491 5) Wiesler, W. T.; Nakanishi, K. ChemInform 1990, 21 (13).

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