Question

Following is a retrosynthesis for the coronary vasodilator ganglefene. CC(C)(C)COC(=O)C(C)(C)C CC(C)COc1ccc(C(=O)O)cc1 CCN(CC)CC(C)C(C)O O=C(O)c1ccc(O)cc1 C=C(C)C(C)=O 4-Hydroxybenzoic acid 3-Methyl-3-buten-2-one (a) Propose a synthesis for ganglefene from 4-hydroxybenzoic acid and 3-methyl-3-buten-2-one. (b) Is ganglefene chiral? If so, which of the possible stereoisomers are formed in this synthesis?

Short answer

Question: Describe the proposed synthesis of ganglefene from 4-hydroxybenzoic acid and 3-methyl-3-buten-2-one, and determine if ganglefene is chiral. Answer: The synthesis of ganglefene can be achieved through the esterification of 4-hydroxybenzoic acid with 3-methyl-3-buten-2-one using a suitable acid catalyst such as sulfuric acid (H2SO4). Ganglefene is not chiral, as it does not have any chiral centers in its structure and has no plane of symmetry. Therefore, there are no stereoisomers formed in this synthesis.

Step-by-step solution

- Understanding the structures of starting materials and the target molecule

Before we dive into the synthesis, it is important to have a clear understanding of the structures of the starting materials and the target molecule. 4-Hydroxybenzoic acid has the formula O=C(O)c1ccc(O)cc1, and 3-Methyl-3-buten-2-one has the formula C=C(C)C(C)=O. Ganglefene has the formula CC(C)(C)COC(=O)C(C)(C)C.

- Planning the synthesis

Given the structural similarities between the starting materials and the target molecule, we can propose a possible route for the synthesis. The proposed synthesis involves the following steps: 1. Perform esterification of 4-hydroxybenzoic acid with 3-methyl-3-buten-2-one to form an ester. 2. Study the stereochemistry of ganglefene to determine if it is chiral and which stereoisomers are formed in this synthesis.

- Esterification of 4-hydroxybenzoic acid with 3-methyl-3-buten-2-one

To synthesize ganglefene, the carboxyl group (COOH) of 4-hydroxybenzoic acid can be converted to an ester by reacting it with the carbonyl group (C=O) of 3-methyl-3-buten-2-one. The reaction can be performed using a suitable acid catalyst such as sulfuric acid (H2SO4). The product of this esterification reaction has the desired structure of ganglefene.

- Determining if ganglefene is chiral and identifying the stereoisomers formed

A molecule is considered chiral if it is non-identical to its mirror image and has no plane of symmetry. Ganglefene does not have any chiral centers in its structure, as all the carbon atoms are either sp2 hybridized or do not have four different groups attached. Therefore, ganglefene is not chiral, and the synthesis does not produce any stereoisomers. In conclusion, the synthesis of ganglefene can be achieved through the esterification of 4-hydroxybenzoic acid with 3-methyl-3-buten-2-one. Ganglefene is not chiral, so there are no stereoisomers formed in this synthesis.