Question

Choose the correct option(s) about reaction sequence : $$ \mathrm{L}_{\mathrm{O}}^{0} \frac{\mathrm{m}-\mathrm{CPBA}}{\longrightarrow}(\mathrm{P}) \stackrel{\mathrm{H}_{3} \mathrm{O}^{+}}{\longrightarrow}(\mathrm{Q}) \stackrel{\Delta}{\longrightarrow}(\mathrm{R}) $$ (A) Formation of (P) involves migration at deficient oxygen (B) (Q) has common name succinic acid (C) Product \((R)\) is O=C1CCC(=O)O1 (D) \(\mathrm{Pr}_{\text {roduct }}(\mathrm{P})\) and \((\mathrm{R})\) are identical

Short answer

The correct options are A, B, and C. Option A is correct because the formation of product P with m-CPBA involves migration at the oxygen site. Option B is correct because compound Q is indeed succinic acid. Option C is correct because the SMILES structure of product R matches that of a cyclic anhydride derived from succinic acid. Option D is incorrect because products P and R have different functional groups.

Step-by-step solution

Option A: Formation of (P) involves migration at deficient oxygen.

Option A states that the formation of product P involves migration at deficient oxygen. This suggests that there is some rearrangement happening in the formation of product P. To determine if this is correct, we need to know the reaction between L-O and m-CPBA. m-CPBA (meta-Chloroperoxybenzoic acid) is an oxidizing agent, capable of converting alkenes to epoxides. Given the "?" on the oxygen of L-O, it is likely that L-O has an alkene functional group. Upon reacting with m-CPBA, the alkene becomes an epoxide, which may involve some migration at the oxygen site. Therefore, option A seems to be correct.

Option B: (Q) has the common name succinic acid.

Option B states that compound Q is succinic acid. Since compound Q is formed by the reaction of compound P with H3O+, let's check if this reaction could lead to succinic acid. Succinic acid has the following structure: HOOC-CH2-CH2-COOH. During the reaction between P (an epoxide) and H3O+, a ring-opening reaction takes place, leading to a diol. If the diol formed has a structure that can undergo further reaction to give succinic acid, then option B is correct.

Option C: Product (R) is O=C1CCC(=O)O1

In Option C, we are given the structure of R in SMILES notation. To check if the structure is correct, we need to see the reaction of Q with heat (Δ). If Q is indeed succinic acid, then heating it would lead to the formation of a cyclic anhydride. Comparing the cyclic anhydride structure to the given SMILES structure in Option C, they both match, which means that Option C is correct.

Option D: Product (P) and (R) are identical.

Option D states that products P and R are identical. From the discussion above, we know that product P is an epoxide formed from the reaction of L-O with m-CPBA, while product R is a cyclic anhydride formed from the reaction of Q (likely succinic acid) with heat. They have different functional groups, so this option is incorrect. In conclusion, options A, B, and C are correct, while option D is incorrect.

Key concepts

m-CPBA Oxidizing Reactions

When it comes to organic chemistry problems, particularly for exams like JEE, understanding the role of m-CPBA is crucial. m-CPBA, or meta-Chloroperoxybenzoic acid, is widely known for its capacity to oxidize alkenes into epoxides. This happens through a reaction mechanism called epoxidation, where the alkene's double bond reacts with the peroxy acid, m-CPBA.

The central reaction involves the transfer of an oxygen atom from m-CPBA to the alkene. It does not require migration at the oxygen site as the reactant already possesses an oxygen atom that forms part of the epoxide ring in the product. Therefore, the statement that involves migration at a deficient oxygen site is not precisely accurate for the formation of epoxides using m-CPBA. This process is stereospecific and retains the configuration of the alkene, producing a three-membered epoxide ring seamlessly.

Epoxide Formation

The formation of epoxides is central to many reactions in organic chemistry. These three-membered cyclic ethers are created by the reaction of an alkene with a peracid, such as m-CPBA. The resulting epoxide can then undergo a variety of reactions, one of the most common being ring-opening.

Detailed knowledge of epoxide formation can help students understand the reactivity of different functional groups and predict the outcomes when an epoxide interacts with other reactants. For instance, in acidic conditions, the ring-opening of epoxides typically leads to trans addition, where the nucleophile and proton add to opposite sides of the epoxide ring. This concept is a gateway to understanding how more complex molecules are constructed from simpler precursors. Students should pay particular attention to stereochemistry in these reactions, as it can significantly affect the properties of the resulting compound.

Succinic Acid

Succinic acid, a four-carbon dicarboxylic acid, is a vital compound to understand in organic chemistry. It can be produced through a variety of processes, including the ring-opening of epoxides in acidic conditions. Students will find this structure's symmetry useful in predicting the compound's behavior in further reactions.

For the students' exercise, succinic acid is understood to be the product formed after an epoxide undergoes acidic hydrolysis. This reaction is possible because of the presence of carboxylic acid groups at both ends, which are added when water, facilitated by an acid catalyst, attacks the less substituted carbon atom of the epoxide ring. Recognizing the foundational structure of succinic acid, HOOC-CH2-CH2-COOH, can help students identify potential products and is essential for discussing the generation of cyclic anhydrides.

Cyclic Anhydride Synthesis

Cyclic anhydride synthesis is a crucial reaction mechanism that students will encounter. It is the process by which two carboxylic acid groups in a dicarboxylic acid, such as succinic acid, react to form a cyclic anhydride. This typically occurs upon heating, which creates an intramolecular reaction that results in water loss and the formation of the anhydride.

Understanding this process helps students appreciate the importance of intramolecular reactions and the conditions under which they take place. Thermodynamically favorable conditions, typically involving heat, push the carboxylic acids to condense. This conversion is a beautiful example of efficiency within organic chemistry, as the molecule reacts with itself, minimizing the need for external reagents or catalysts. The formation of cyclic anhydrides often introduces new synthetic pathways in complex organic synthesis, illustrating the interconnectedness of organic transformations.