Chem 313, Problem Set #4, 2010
Problem 1. A) draw the chair conformation. B) draw the Fischer projection. C) Draw the
Haworth projection of the major cyclic form. D) Convert the Zig-Zag projection into a
Fischer projection. E) Convert the Reeves projection into a closed Fischer projection. F)
Fill in the Fischer projection for L-Glucose and draw its cyclic form in a chair projection.
G) Draw the Fischer projection for Beta-L-Glucofuranose and its respective Haworth
configuration. Problem 2. Provide the structure of the product of the following reactions: Problem 3. Show the steps and products of the Kiliani-Fischer procedure, starting from
D-xylose. Predict the major and minor products formed.
Problem 4. alpha-D-mannose has a specific rotation of +29.3˚. beta-D-mannose has a
specific rotation of -17.0˚. Over time, a sample of either the alpha or beta anomer in
water will have a specific rotation of +14.5˚. With a mechanism, explain what is
happening. Write a mechanism to explain what is happening. What percentage of each
anomer exists at equilibrium? Why is one favored over the other?
Both alpha and beta mannose are undergoing mutaro