Organic Chemistry (9th Edition)
9th Edition
ISBN: 9780321971371
Author: Leroy G. Wade, Jan W. Simek
Publisher: PEARSON
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Textbook Question
Chapter 18, Problem 18.73SP
The mass spectrum of unknown compound A shows a molecular ion at m/z 116 and prominent peaks at m/z 87 and m/z 101. Its UV spectrum shows no maximum above 200 nm. The IR and NMR spectra of A follow. When A is washed with dilute aqueous acid, extracted into dichloromethane, and the solvent evaporated, it gives a product B. B shows a strong carbonyl signal at 1715cm−1 in the IR spectrum and a weak maximum at 274 nm (ε=16) in the UV spectrum. The mass spectrum of B shows a molecular ion of m/z 72. Determine the structures of A and B, and show the fragmentation to account for the peaks at m/z 87 and 101.
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Chapter 18 Solutions
Organic Chemistry (9th Edition)
Ch. 18.3 - Give the IUPAC name and (if possible) a common...Ch. 18.5D - NMR spectra for two compounds are given here,...Ch. 18.5D - Why were no products from the McLafferty...Ch. 18.5D - Use equations to show the fragmentation leading to...Ch. 18.5E - Prob. 18.5PCh. 18.7D - Show how you would synthesize each compound from...Ch. 18.8 - Prob. 18.7PCh. 18.9 - Predict the products of the following reactions....Ch. 18.9 - Show how the following transformations may be...Ch. 18.10 - Prob. 18.10P
Ch. 18.11 - Show how you would accomplish the following...Ch. 18.11 - Prob. 18.12PCh. 18.12 - Propose mechanisms for a. the acid-catalyzed...Ch. 18.12 - Rank the following compounds in order of...Ch. 18.13 - Prob. 18.15PCh. 18.13 - Show how you would accomplish the following...Ch. 18.14 - Prob. 18.17PCh. 18.14 - Prob. 18.18PCh. 18.14 - Prob. 18.19PCh. 18.14 - Prob. 18.20PCh. 18.15 - 2,4-Dinitrophenylhydrazine is frequently used for...Ch. 18.15 - Prob. 18.22PCh. 18.15 - Prob. 18.23PCh. 18.16 - Prob. 18.24PCh. 18.16 - Prob. 18.25PCh. 18.16 - Show what alcohols and carbonyl compounds give the...Ch. 18.16 - In the mechanism for acetal hydrolysis shown, the...Ch. 18.16 - Prob. 18.28PCh. 18.17 - Show how you would accomplish the following...Ch. 18.18 - Prob. 18.30PCh. 18.18 - Prob. 18.31PCh. 18.18 - Prob. 18.32PCh. 18.18 - Show how Wittig reactions might be used to...Ch. 18.19 - Predict the major products of the following...Ch. 18.20C - Prob. 18.35PCh. 18.20C - Predict the major products of the following...Ch. 18 - Draw structures of the following derivatives. a....Ch. 18 - Prob. 18.38SPCh. 18 - Predict the major products of the following...Ch. 18 - Rank the following carbonyl compounds in order of...Ch. 18 - Acetals can serve as protecting groups for...Ch. 18 - Sketch the expected proton NMR spectrum of...Ch. 18 - A compound of formula C6H10O2 shows only two...Ch. 18 - The proton NMR spectrum of a compound of formula...Ch. 18 - The following compounds undergo McLafferty...Ch. 18 - An unknown compound gives a molecular ion of m/z...Ch. 18 - Show how you would accomplish the following...Ch. 18 - Prob. 18.48SPCh. 18 - Prob. 18.49SPCh. 18 - Propose mechanisms for the following reactions.Ch. 18 - Show how you would accomplish the following...Ch. 18 - Show how you would synthesize the following...Ch. 18 - Predict the products formed when cyclohexanone...Ch. 18 - Predict the products formed when...Ch. 18 - Show how you would synthesize octan-2-one from...Ch. 18 - Prob. 18.56SPCh. 18 - Both NaBH4 and NaBD4 are commercially available,...Ch. 18 - When LiAIH4 reduces 3-methylcyclopentanone, the...Ch. 18 - Prob. 18.59SPCh. 18 - Show how you would accomplish the following...Ch. 18 - There are three dioxane isomers 1,2-dioxane,...Ch. 18 - Two structures for the sugar glucose are shown on...Ch. 18 - Prob. 18.63SPCh. 18 - Prob. 18.64SPCh. 18 - Prob. 18.65SPCh. 18 - Prob. 18.66SPCh. 18 - Within each set of structures, indicate which will...Ch. 18 - Prob. 18.68SPCh. 18 - Prob. 18.69SPCh. 18 - Prob. 18.70SPCh. 18 - The UV spectrum of an unknown compound shows...Ch. 18 - a. Simple aminoacetals hydrolyze quickly and...Ch. 18 - The mass spectrum of unknown compound A shows a...Ch. 18 - Prob. 18.74SPCh. 18 - Prob. 18.75SPCh. 18 - Prob. 18.76SPCh. 18 - Prob. 18.77SP
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