What is the product formed
Answers
Answer:
Whoa this is a scary question, but I'll try it out. Hope it turns out right.
Whenever I solve organic chemistry questions, I go to the basic reagents and use basic reactions to determine the functional group of the products.
In aldol condensation, we need α- H on the carbon beside the carbonyl carbon.
Our reaction is as follows-
We take two molecules of the carbonyl compounds with α- H and from the first molecule we eliminate the oxygen and from the second molecule we eliminate two α- H. So in all, there is a loss of one water molecule. The resultant is a compound with a double bond right between the carbons where the elimination has occurred.
Instead of two molecules, in this case there are two such carbonyl carbons in the same molecule. So we perform the elimination by cyclizing this molecule in a way such that the two carbons with =O come adjacent to one another.
Basically with trial and error, if we make a cyclic compound with our given data, there should be a double bond between the second and seventh carbons ( of the acyclic compound ) and there should be a methyl branching on the fifth carbon( of the acyclic compound ). The =O in the product appears on the α-C ( refer to the simplest molecule crotonaldehyde- made by the aldol condensation of acetaldehyde ).
This means that we need to have a three carbon gap between the double bonded carbon and the carbon with a methyl branch.
This is clearly the case in (a) and (d).
We also need to have four carbons between the two double bonded carbons. This is the case in (d) only. Therefore, (d) should be our answer.
My answer's pretty late, but I hope it clarifies this question.