ORGANIC CHEMISTRY
5th Edition
ISBN: 9781259977596
Author: SMITH
Publisher: MCG
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 28, Problem 28.26P
Interpretation Introduction
(a)
Interpretation: The aldoses formed when D-threose is subjected to the Kiliani–Fischer synthesis are to be predicted.
Concept introduction: Kiliani–Fischer synthesis is a method which is used for the elongation of the carbon chains in aldose. In this method, the aldose chain is elongated by the formation of new stereogenic centre at
Interpretation Introduction
(b)
Interpretation: The aldoses formed when D-ribose is subjected to the Kiliani–Fischer synthesis are to be predicted.
Concept introduction: Kiliani–Fischer synthesis is a method which is used for the elongation of the carbon chains in aldose. In this method, the aldose chain is elongated by the formation of new stereogenic centre at
Interpretation Introduction
(c)
Interpretation: The aldoses formed when D-galactose is subjected to the Kiliani–Fischer synthesis are to be predicted.
Concept introduction: Kiliani–Fischer synthesis is a method which is used for the elongation of the carbon chains in aldose. In this method, the aldose chain is elongated by the formation of new stereogenic centre at
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
What aldoses are formed when the following aldoses are subjected to the Kiliani-Fischer
synthesis: (a) D-threose; (b) D-ribose; (c) D-galactose?
26. This compound is L-glyceraldehyde. Draw a stereochemically correct representation of C-1
and C-2 of D-glucose.
CHO
|
HO—C—H
|
CH2OH
27. Categorize each of the following as an aldose, a ketose, or neither.
28. Define each in 20 words or less:
(a) anomeric carbon;
(b) enantiomers;
(c) furanose and pyranose;
(d) glycoside;
(e) aldose and ketose.
29. A) Draw the structure of any aldohexose in the pyranose ring form. B) Draw the structure of
the anomer of the aldohexose you drew above. C) How many asymmetric carbons (chiral
centers) does each of these structures have? D) How many stereoisomers of the aldohexoses
you drew are theoretically possible?
30. A) Define "reducing sugar." (b) Sucrose is a disaccharide composed of glucose and fructose
(Glc(1 → 2)Fru). Explain why sucrose is not a reducing sugar, even though both glucose
and fructose are.
(d) Draw the structure of the expected product when monosaccharide B undergo
mutarotation upon dissolving in water in the presence of Tollens reagent (AGNO3,
NHẠOH).
он
OH
O.
OH
OH
OH
monosaccharide B
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 - Prob. 28.17PCh. 28 - Draw a stepwise mechanism for the following...Ch. 28 - Prob. 28.19PCh. 28 - Prob. 28.20PCh. 28 - Prob. 28.21PCh. 28 - Prob. 28.22PCh. 28 - Draw the products formed when D-arabinose is...Ch. 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 - 28.40 Convert each compound to a Fischer...Ch. 28 - Prob. 28.41PCh. 28 - Prob. 28.42PCh. 28 - 28.43 Draw a Haworth projection for each compound...Ch. 28 - Prob. 28.44PCh. 28 - 28.45 Draw both pyranose anomers of each...Ch. 28 - Prob. 28.46PCh. 28 - Prob. 28.47PCh. 28 - Prob. 28.48PCh. 28 - Prob. 28.49PCh. 28 - 28.50 Draw the products formed when D-altrose is...Ch. 28 - Prob. 28.51PCh. 28 - Prob. 28.52PCh. 28 - Prob. 28.53PCh. 28 - Prob. 28.54PCh. 28 - Prob. 28.55PCh. 28 - Prob. 28.56PCh. 28 - Prob. 28.57PCh. 28 - 28.58 Draw a stepwise mechanism for the following...Ch. 28 - Prob. 28.59PCh. 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 - 28.71 Draw a stepwise mechanism for the following...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- (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?arrow_forwarda) The D-aldopentose A, C5H1005, reacts with HNO3 to yield an optically active aldaric acid B. Kiliani-Fischer chain extension of A produces a pair of D-aldohexoses C and D. C is converted by HNO3 to an optically active aldaric acid, but D is converted by HNO3 to an optically inactive aldaric acid. Write acyclic Fischer projections for A, B, C, D. b) Disaccharide E is a reducing sugar. It is hydrolyzed by an α-glycosidase enzyme, which means it contains an α- glycoside link. Treatment of E with Ag2O and excess Mel gives an octamethyl derivative F. Hydrolysis of F in dilute aqueous acid gives the pair of molecules shown below. Write the structures of E and F. (If the stereochemistry at a particular carbon is not determined by the above data, indicate this with a wavy line as shown below.) HO OMe OMe MeO MeO MOH OMe mOH OMe OMearrow_forwarda) The D-aldopentose A, C5H1005, reacts with HNO3 to yield an optically active aldaric acid B. Kiliani-Fischer chain extension of A produces a pair of D-aldohexoses C and D. C is converted by HNO3 to an optically active aldaric acid, but D is converted by HNO3 to an optically inactive aldaric acid. Write acyclic Fischer projections for A, B, C, D.arrow_forward
- A D-aldopentose A is reduced to an optically active alditol. Upon Kiliani–Fischer synthesis, A is converted to two D-aldohexoses, 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?arrow_forwardA D-aldopentose A is oxidized to an optically inactive aldaric acid with HNO3. A is formed by the Kiliani–Fischer synthesis of a D-aldotetrose B, which is also oxidized to an optically inactive aldaric acid with HNO3. What are the structures of A and B?arrow_forwardThe anticoagulant heparin is a polysaccharide that contains alternating residues of -D- glucuronic acid-6- sulfate and N-sulfo-D-glucosamine-6sulfate connected by (1 B 4)- glycosidic linkages. Draw a part of heparin that shows one each of the two residues.arrow_forward
- 1. Draw Haworth projections of B-D-arabinofuranose and a-L-mannopyranose. 2. Consider the structure of the disaccharide drawn at right: НО `CH2 В ОН (a) Give the names and D/L designation for the two monosaccharides linked together. H,C-O OHO „OH OH А: НО НО A В: ОН (b) In the structure, circle the anomeric carbon of each saccharide. (c) Is each saccharide present in its a or ß anomer? Specify both A and B (d) Would this disaccharide undergo mutarotation? Why or why not? (e) Would this disaccharide react with Tollens and/or Benedicts reagent? Why or why not? (f) There are two reasons this is very unlikely to be a naturally occurring disaccharide. What about its structure suggests this is true? Give both reasons.arrow_forwardA D-aldohexose A is formed from an aldopentose B by the Kiliani-Fischer synthesis. Reduction of A with NABH4 forms an optically inactive alditol. Oxidation of B forms an optically active aldaric acid. What are the structures of A and B?arrow_forwardGiven the following structure of aldose, (a) how many chiral carbons are there? (b) is it a reducing sugar? and (c) is it an L or D sugar?arrow_forward
- Treatment with NaBH 4 converts aldose U into an optically inactive (meso) alditol V. Ruff degradation ofU gives W, whose alditol is optically inactive. Ruff degradation of W forms D-glyceraldehyde, thesimplest aldose. Upon Kiliani-Fischer synthesis, U is converted to two aldoses, X and Y. X is oxidized toan optically active aldaric acid Z. Y is oxidized to an optically inactive aldaric acid. Draw the structuresof D-glyceraldehyde, V, W, X, Y, and Z. Structure of compound U is shown below.arrow_forwardAlthough reaction occurs in sugars also. H, OH H H-C-OH Oxidizing agent OH OH Н-С-ОН Н-С-ОН C=0 R OH R R R Aldose Aldonic acid anion Ketose Enediol Copyright © 2007 Pearson Prentice Hall, Inc. Draw the reaction above substituting D-fructose instead of the generalized ketose structure shown above (you need to draw all 4 structures). Slan and upload your drawing.arrow_forwardIdentify compounds A–D. A D-aldopentose A is oxidized with HNO3 to an optically inactive aldaric acid B. A undergoes the Kiliani–Fischer synthesis to yield C and D. C is oxidized to an optically active aldaric acid. D is oxidized to an optically inactive aldaric acidarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Introduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage Learning
Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning
Introduction to General, Organic and Biochemistry
Chemistry
ISBN:9781285869759
Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres
Publisher:Cengage Learning
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning