Organic Chemistry (9th Edition)
9th Edition
ISBN: 9780321971371
Author: Leroy G. Wade, Jan W. Simek
Publisher: PEARSON
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Chapter 13, Problem 13.55SP
Phenyl Grignard reagent adds to 2-methylpropanal to give the secondary alcohol shown. The proton NMR of 2-methylpropanal shows the two methyl groups as equivalent (one doublet at δ 1.1), yet the product alcohol, a racemic mixture, shows two different 3H doublets, one at δ 0.75 and one around δ 1.0.
- a. Draw a Newman projection of the product along the C1-C2 axis.
- b. Explain why the two methyl groups have different NMR chemical shifts. What is the term applied to protons such as these?
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Chapter 13 Solutions
Organic Chemistry (9th Edition)
Ch. 13.5A - In a 300-MHz spectrometer, the protons in...Ch. 13.5B - Prob. 13.2PCh. 13.6 - Determine the number of different kinds of protons...Ch. 13.6 - Prob. 13.4PCh. 13.7 - Draw the integral trace expected for the NMR...Ch. 13.7 - Prob. 13.6PCh. 13.8C - Draw the NMR spectra you would expect for the...Ch. 13.8D - Draw the NMR spectra you expect for the following...Ch. 13.8D - a. Assign protons to the peaks in the NMR spectrum...Ch. 13.8D - Prob. 13.10P
Ch. 13.8D - Two spectra are shown. Propose a structure that...Ch. 13.9 - Prob. 13.12PCh. 13.9 - The spectrum of trans-hex-2-enoic acid follows. a....Ch. 13.9 - Prob. 13.14PCh. 13.9 - Prob. 13.15PCh. 13.10 - Prob. 13.16PCh. 13.10 - If the imaginary replacement of either of two...Ch. 13.10 - Predict the theoretical number of different NMR...Ch. 13.11B - Prob. 13.19PCh. 13.11B - Prob. 13.20PCh. 13.11B - Prob. 13.21PCh. 13.11B - Prob. 13.22PCh. 13.11B - Prob. 13.23PCh. 13.11B - Prob. 13.24PCh. 13.12E - Draw the expected broadband-decoupled 13 C N M R...Ch. 13.12E - a. Show which carbon atoms correspond with which...Ch. 13.12E - Repeat Problem13-25, sketching the...Ch. 13.12F - Prob. 13.28PCh. 13.13 - A bottle of allyl bromide was found to contain a...Ch. 13.13 - A laboratory student was converting cyclohexanol...Ch. 13.14 - Sets of spectra are given for two compounds. For...Ch. 13 - An unknown compound has the molecular formula C 9...Ch. 13 - Prob. 13.34SPCh. 13 - Predict the approximate chemical shifts of the...Ch. 13 - Prob. 13.36SPCh. 13 - Prob. 13.37SPCh. 13 - Prob. 13.38SPCh. 13 - Prob. 13.39SPCh. 13 - Prob. 13.40SPCh. 13 - For each compound shown below. 1. sketch the 13 C...Ch. 13 - Prob. 13.42SPCh. 13 - Prob. 13.43SPCh. 13 - Prob. 13.44SPCh. 13 - Prob. 13.45SPCh. 13 - Prob. 13.46SPCh. 13 - A compound was isolated as a minor constituent in...Ch. 13 - Prob. 13.48SPCh. 13 - The three isomers of dimethylbenzene are commonly...Ch. 13 - a. Draw all six isomers of formula C 4 H 8...Ch. 13 - Prob. 13.51SPCh. 13 - Hexamethylbenzene undergoes free-radical...Ch. 13 - Each of these four structures has molecular...Ch. 13 - Prob. 13.54SPCh. 13 - Phenyl Grignard reagent adds to 2-methylpropanal...Ch. 13 - Prob. 13.56SP
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