Q70E - Organic Chemistry (Mcmurry)

Question

Predict the product(s) if the starting materials below underwent a Claisen rearrangement. Draw arrows to illustrate the rearrangement of electrons.

(a)

(b)

(c)

Step-by-Step Solution

Answer

The answer is 

(a)

(b)

(c)

Step 1: Claisen rearrangement

The Claisen rearrangement is a reaction of unsaturated compounds that takes place in the presence of heat. It is also called the (3,3) rearrangement.

Step 2: Subpart (a)

The product of the reaction is shown below.

                                                  Reaction (a)

The reaction involves the rearrangement of electrons in presence of heat to give an unsaturated cyclic ketone.

Step 3: Subpart (b)

The product of the reaction is shown below.

                                                        Reaction (b)

In this reaction, rearrangement gives an unsaturated aldehyde containing Deuterium.

Step 4: Subpart (c)

The product of the reaction is shown below.

                                                  Reaction (c)

The reaction involves the rearrangement of the reactant to give a cyclic unsaturated ketone.