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Structures and Natural Products

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11. Refer to Exhibit 9-7. Two structures have been proposed for this natural product. Circle the structure that is consistent with the information presented and briefly explain your choice.

12. Draw a structure for a singly substituted chiral chloroalkane that contains four carbon atoms with R stereochemistry. Indicate the chirality center with an asterisk.

14. Refer to Exhibit 5-7.
a. The structures attached show the step-wise bond making and bond breaking in this reaction. Daw curved arrows to show the electron flow that has occurred in each step.
b. Calculate K for the reaction in part a.
c. Calculate dG for the reaction in part a.

25. We will learn next semester that the addition of a Grignard reagent (HH3CH2MgBr) to acetophenone gives a tertiary alcohol. Assuming addition of the Grignard reagent occurs from the Re-face, draw the product with the proper stereochemistry.

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11. The cyclic compound is achiral due to a plane of symmetry present in the molecule. Hence it cannot have optical activity. This makes the 2nd compound ...

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The structures and natural products are examined in the solution.

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Organic Chemistry Synthesis Reactions and Stereochemistry

Please see the attached file for the complete problems.

1. Predict the product of the reaction below. Be sure to indicate stereochemistry when appropriate.

2. Provide proper IUPAC names for each compound below.

3. The compound below has been isolated from the safflower plant. Consider its structure to
answer the following questions.

4. What is the molecular formula for this natural product?

5. What is the degree of unsaturation for this compound?

6. Assign E or Z configuration to each of the double bonds in the compound.

7. Consider an unknown with the molecular formula C4H6. How many degrees of unsaturation are present?

8. Select the best reagent or sequence of reagents from the list provided which would best
accomplish each transformation below. Place the letter corresponding to the reagent(s) in the
blank to the left of each reaction. Each transformation requires only one answer.
a) H2SO4, H2O, HgSO4
b) H2, Lindlar
c) 1. BH3, THF
2. H2O2
d) 1. NaNH2, NH3
2. CH3CH2I
e) 1. Br2, CCl4
2. 2 NaNH2, NH3
f) 1. HCl
2. NaNH2, NH3
g) Li/NH3
h) 1. NaNH2, NH3

9. The intermediate in the first step of this reaction sequence is called a

a. carbocation
b. cyclonium ion
c. mercurinium ion
d. mercapto species.

10. In an abandoned laboratory has been found a flammable liquid, A, in a bottle bearing only the label "Compound A: ." Compound A reacts with 1 mol equiv of hydrogen and, after treatment with acidic , gives the dicarboxylic acid C (see below). Another bottle from the same laboratory is labeled "Compound B (isomer of A)." Compound B also reacts with 1 mol equiv of hydrogen, but yields cyclohexanone after treatment with acidic .

How many degrees of Unsaturation does compound A possess?

Suggest structures for A and B.

What was the other product formed in the KmnO4 oxidation of B?

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