ORGANIC CHEMISTRY-ACCESS
6th Edition
ISBN: 9781260475586
Author: SMITH
Publisher: MCG
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Chapter 26, Problem 66P
Interpretation Introduction
Interpretation: The structures of A-C are to be predicted.
Concept introduction: The optically active compounds should not have plane of symmetry and center of symmetry. A point is said to be center of symmetry, if same molecules are present in the opposite direction to each other. If plane passes through the center of the molecule and the molecule is divided into two equal halves, then the molecule is said to have a plane of symmetry.
Kilani-Fischer synthesis results in the formation of two epimers. Two compounds which are neither superimposable nor mirror images to each other and the configuration of one of their stereogenic centers is different are known as epimers.
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A D-aldopentose A is reduced to an optically active alditol. Upon Kiliani–Fischer synthesis, A is converted to two Daldohexoses, B and C. B is oxidized to an optically inactive aldaric acid. C is oxidized to an optically active aldaric acid. What are the structures of A–C?
A D-aldohexose A is formed from an aldopentose B by the Kiliani-Fischer synthesis. Reduction of
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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
Chapter 26 Solutions
ORGANIC CHEMISTRY-ACCESS
Ch. 26.2 - Prob. 1PCh. 26.2 - Prob. 2PCh. 26.2 - Label each stereogenic center as R or S. a. b. c....Ch. 26.2 - Convert the ball-and-stick model to a Fischer...Ch. 26.2 - Prob. 5PCh. 26.2 - Prob. 6PCh. 26.3 - Prob. 7PCh. 26.3 - Prob. 8PCh. 26.4 - Prob. 9PCh. 26.4 - Prob. 10P
Ch. 26.6 - Prob. 11PCh. 26.6 - Prob. 12PCh. 26.6 - Prob. 13PCh. 26.6 - Prob. 14PCh. 26.6 - Prob. 15PCh. 26.7 - Prob. 16PCh. 26.7 - Draw a stepwise mechanism for the following...Ch. 26.7 - Prob. 18PCh. 26.8 - Prob. 19PCh. 26.9 - Prob. 20PCh. 26.9 - Prob. 21PCh. 26.9 - Draw the products formed when D-arabinose is...Ch. 26.9 - Prob. 23PCh. 26.10 - Prob. 24PCh. 26.10 - Prob. 25PCh. 26.10 - Prob. 26PCh. 26.10 - Prob. 27PCh. 26.11 - Prob. 28PCh. 26.11 - Prob. 29PCh. 26.12 - Prob. 30PCh. 26.12 - Prob. 31PCh. 26.13 - Prob. 32PCh. 26.13 - Prob. 33PCh. 26.13 - Problem-28.35
Draw the structures of the...Ch. 26.13 - Prob. 35PCh. 26 - 28.37 Convert each ball-and-stick model to a...Ch. 26 - Prob. 37PCh. 26 - Prob. 38PCh. 26 - 28.40 Convert each compound to a Fischer...Ch. 26 - Prob. 40PCh. 26 - Prob. 41PCh. 26 - 28.43 Draw a Haworth projection for each compound...Ch. 26 - Prob. 43PCh. 26 - 28.45 Draw both pyranose anomers of each...Ch. 26 - Prob. 45PCh. 26 - 28.50 Draw the products formed when D-altrose is...Ch. 26 - 28.58 Draw a stepwise mechanism for the following...Ch. 26 - Prob. 62PCh. 26 - Prob. 63PCh. 26 - Prob. 64PCh. 26 - Prob. 65PCh. 26 - Prob. 66PCh. 26 - Prob. 67PCh. 26 - Prob. 68PCh. 26 - Prob. 69PCh. 26 - Prob. 70P
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