Organic Chemistry
6th Edition
ISBN: 9781936221349
Author: Marc Loudon, Jim Parise
Publisher: W. H. Freeman
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Question
Chapter 24, Problem 24.27P
Interpretation Introduction
Interpretation:
The structures of A, B and C are to be drawn.
Concept introduction:
A method through which the aldonic acids are reduced to aldoses is known as Kiliani-Fischer synthesis. The synthesis consists of three processes, the formation of cyanohydrins, hydrolysis and the reduction.
A pair of stereoisomer in which there is a difference in configuration at stereogenic centre is known as epimer.
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An aldose A, is reduced by sodium borohydride to an optically inactive alditol B. The Ruff degredation of A forms C. Oxidation of C by nitric acid generates the optically inactive diacid D. The ruff degreation of C forms D-glyceraldehyde. draw the structures for compounds A through D and discuss a mechanism for the reduction step using sodium borohydride
(a) Which of the d-aldopentoses will give optically active aldaric acids on oxidation with HNO3 ?(b) Which of the d-aldotetroses will give optically active aldaric acids on oxidation with HNO3 ?(c) Sugar X is known to be a d-aldohexose. On oxidation with HNO3, X gives an optically inactive aldaric acid. WhenX is degraded to an aldopentose, oxidation of the aldopentose gives an optically active aldaric acid. Determine thestructure of X.(d) Even though sugar X gives an optically inactive aldaric acid, the pentose formed by degradation gives an opticallyactive aldaric acid. Does this finding contradict the principle that optically inactive reagents cannot form opticallyactive products?(e) Show what product results if the aldopentose formed from degradation of X is further degraded to an aldotetrose.Does HNO3 oxidize this aldotetrose to an optically active aldaric acid?
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Chapter 24 Solutions
Organic Chemistry
Ch. 24 - Prob. 24.1PCh. 24 - Prob. 24.2PCh. 24 - Prob. 24.3PCh. 24 - Prob. 24.4PCh. 24 - Prob. 24.5PCh. 24 - Prob. 24.6PCh. 24 - Prob. 24.7PCh. 24 - Prob. 24.8PCh. 24 - Prob. 24.9PCh. 24 - Prob. 24.10P
Ch. 24 - Prob. 24.11PCh. 24 - Prob. 24.12PCh. 24 - Prob. 24.13PCh. 24 - Prob. 24.14PCh. 24 - Prob. 24.15PCh. 24 - Prob. 24.16PCh. 24 - Prob. 24.17PCh. 24 - Prob. 24.18PCh. 24 - Prob. 24.19PCh. 24 - Prob. 24.20PCh. 24 - Prob. 24.21PCh. 24 - Prob. 24.22PCh. 24 - Prob. 24.23PCh. 24 - Prob. 24.24PCh. 24 - Prob. 24.25PCh. 24 - Prob. 24.26PCh. 24 - Prob. 24.27PCh. 24 - Prob. 24.28PCh. 24 - Prob. 24.29PCh. 24 - Prob. 24.30PCh. 24 - Prob. 24.31PCh. 24 - Prob. 24.32PCh. 24 - Prob. 24.33PCh. 24 - Prob. 24.34APCh. 24 - Prob. 24.35APCh. 24 - Prob. 24.36APCh. 24 - Prob. 24.37APCh. 24 - Prob. 24.38APCh. 24 - Prob. 24.39APCh. 24 - Prob. 24.40APCh. 24 - Prob. 24.41APCh. 24 - Prob. 24.42APCh. 24 - Prob. 24.43APCh. 24 - Prob. 24.44APCh. 24 - Prob. 24.45APCh. 24 - Prob. 24.46APCh. 24 - Prob. 24.47APCh. 24 - Prob. 24.49APCh. 24 - Prob. 24.50APCh. 24 - Prob. 24.51APCh. 24 - Prob. 24.52APCh. 24 - Prob. 24.53APCh. 24 - Prob. 24.54APCh. 24 - Prob. 24.55APCh. 24 - Prob. 24.56APCh. 24 - Prob. 24.57APCh. 24 - Prob. 24.58APCh. 24 - Prob. 24.59APCh. 24 - Prob. 24.60APCh. 24 - Prob. 24.61APCh. 24 - Prob. 24.62AP
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