Organic Chemistry
4th Edition
ISBN: 9780073402772
Author: Janice G. Smith
Publisher: MCG
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Chapter 28, Problem 28.66P
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?
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Chapter 28 Solutions
Organic Chemistry
Ch. 28 - Prob. 28.1PCh. 28 - Prob. 28.2PCh. 28 - Label each stereogenic center as R or S. a. b. c....Ch. 28 - Convert the ball-and-stick model to a Fischer...Ch. 28 - Prob. 28.5PCh. 28 - Prob. 28.6PCh. 28 - Prob. 28.7PCh. 28 - Prob. 28.8PCh. 28 - Prob. 28.9PCh. 28 - Prob. 28.10P
Ch. 28 - Prob. 28.11PCh. 28 - Prob. 28.12PCh. 28 - Prob. 28.13PCh. 28 - Prob. 28.14PCh. 28 - Prob. 28.15PCh. 28 - Prob. 28.16PCh. 28 - Draw a stepwise mechanism for the following...Ch. 28 - Prob. 28.18PCh. 28 - Prob. 28.19PCh. 28 - Prob. 28.20PCh. 28 - Prob. 28.21PCh. 28 - Draw the products formed when D-arabinose is...Ch. 28 - Prob. 28.23PCh. 28 - Prob. 28.24PCh. 28 - Prob. 28.25PCh. 28 - Prob. 28.26PCh. 28 - Prob. 28.27PCh. 28 - Prob. 28.28PCh. 28 - Prob. 28.29PCh. 28 - Prob. 28.30PCh. 28 - Prob. 28.31PCh. 28 - Prob. 28.32PCh. 28 - Prob. 28.33PCh. 28 - Prob. 28.34PCh. 28 - Problem-28.35
Draw the structures of the...Ch. 28 - Prob. 28.36PCh. 28 - 28.37 Convert each ball-and-stick model to a...Ch. 28 - Prob. 28.38PCh. 28 - Prob. 28.39PCh. 28 - Convert each compound to a Fischer projection and...Ch. 28 - Prob. 28.41PCh. 28 - Prob. 28.42PCh. 28 - Prob. 28.43PCh. 28 - Prob. 28.44PCh. 28 - Prob. 28.45PCh. 28 - Draw both pyranose anomers of each aldohexose...Ch. 28 - Prob. 28.47PCh. 28 - Prob. 28.48PCh. 28 - Prob. 28.49PCh. 28 - Prob. 28.50PCh. 28 - Prob. 28.51PCh. 28 - Prob. 28.52PCh. 28 - Prob. 28.53PCh. 28 - What products are formed when each compound is...Ch. 28 - Prob. 28.55PCh. 28 - Prob. 28.56PCh. 28 - Prob. 28.57PCh. 28 - Prob. 28.58PCh. 28 - 28.58 Draw a stepwise mechanism for the following...Ch. 28 - Prob. 28.60PCh. 28 - Prob. 28.61PCh. 28 - Prob. 28.62PCh. 28 - Prob. 28.63PCh. 28 - Prob. 28.64PCh. 28 - Prob. 28.65PCh. 28 - Prob. 28.66PCh. 28 - Prob. 28.67PCh. 28 - Prob. 28.68PCh. 28 - Prob. 28.69PCh. 28 - Prob. 28.70PCh. 28 - Prob. 28.71PCh. 28 - Prob. 28.72PCh. 28 - Prob. 28.73PCh. 28 - Prob. 28.74PCh. 28 - Prob. 28.75PCh. 28 - Prob. 28.76PCh. 28 - Prob. 28.77PCh. 28 - Draw a stepwise mechanism for the following...Ch. 28 - Prob. 28.79P
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- When d-glucose is reduced with sodium borohydride, optically active glucitol results.When optically active d-galactose is reduced, however, the product is optically inactive.Explain this loss of optical activityarrow_forwardRaffinose is a trisaccharide (C18H32O16) isolated from cottonseed meal. Raffinose doesnot reduce Tollens reagent, and it does not mutarotate. Complete hydrolysis of raffinosegives d-glucose, d-fructose, and d-galactose. When raffinose is treated with invertase,the products are d-fructose and a reducing disaccharide called melibiose. Raffinose isunaffected by treatment with a b@galactosidase, but an a@galactosidase hydrolyzes itto d-galactose and sucrose. When raffinose is treated with dimethyl sulfate and basefollowed by hydrolysis, the products are 2,3,4-tri-O-methylglucose, 1,3,4,6-tetraO-methylfructose, and 2,3,4,6-tetra-O-methylgalactose. Determine the completestructures of raffinose and melibiose, and give a systematic name for melibiose.arrow_forwardDraw the structure of: (a) a polysaccharide formed by joining D-mannose units in 1->4-ß-glycosidic linkages; (b) a polysaccharide formed by joining D-glucose units in 1->6-a-glycosidic linkages. The polysaccharide in (b) is dextran, a component of dental plaque.arrow_forward
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