solutions to problems condensation reactions i, building bridges to knowledge

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Solutions to Problems Condensation Reactions

Building Bridges to Knowledge

Photo the Shanghai Shoreline

1. Suggest products for (a) - (f), and suggest IUPAC names for the products of (a) - (e).

(a)

3-hydroxybutanal

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(b)

3-hydroxy-2-methylbutanal (c)

2-ethyl-3-hydroxybutanal (d)

3-hydroxy-2-methyl-3-phenylpropanal

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(e)

2,4-dicyclohexyl-3-hydroxybutanal

(f)

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2. Suggest a synthesis for the following compound from the indicated starting material and any necessary organic or inorganic materials.

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3. Suggest a synthesis for the following compound from the

indicated starting materials and any necessary inorganic materials.

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4. The following sequence of reactions leads to the formation of compound I.

Compound I

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mechanism for the formation of compound A. (1)

(2)

5. Suggest a product for the following reaction, and

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suggest a mechanism for the reaction. (1)

(2)

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(3)

(4)

(5)

6. Suggest a series of elementary steps to rationalize the formation of

the following transformation.

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The balanced chemical equation for the base-catalyzed reaction is:

(1)

+ H2O (2)

(3)

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(4)

+ - OH 7. Suggest a mechanism for the following transformation.

The balanced chemical equation is:

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(1)

+ H2O (2)

8. Suggest a mechanism for the following acid catalyzed reaction.

(1)

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(2)

(3)

(4)

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(5)

(6)

8. Using the cyclohexane-like chair conformation, suggest a

series of elementary steps to rationalize the following transformation.

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(1)

+ H2O (2)

(3)

The formation of the double bond (the elimination reaction) would proceed through the following steps: (1)

(2)

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(3)

10, Suggest a synthesis for the following from the indicated starting

material and any other necessary organic or inorganic compounds.

Step 1

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Step 2: treat the resulting beta hydroxy ketone with acid and heat to form the elimination product.

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11. Suggest structures for A, B, C6H12O2

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12. Suggest a synthesis for Compound III from compound I,

compound II and any necessary inorganic materials.

compound III

compound I compound II

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13. Yotes and Anderson reported the following transformation in the Journal of the American Chemical Society.

The reaction takes place in two steps. Step 1 is treatment with base:

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Step 2 is acidification of the resulting salt:

Suggest a series of elementary steps that could account for this transformation. (1)

(2)

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(3)

(4)

(5)

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(6)

(7)

(8)

(9)

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After the salt is formed, then it is acidified to form the carboxylic acid.