Question

CC(C)=C(C)O (D) C#CCC(=O)[O-] # In this given reaction sequence Pis (A) C=CCCC=O (B) C=CC(C)=O (C) C#CC(C)=C(C)O (D) C#CCC(=O)[O-]

Short answer

The given reaction sequence involves three main transformations: 1. Hydroboration-oxidation of A (C=CCCC=O) to produce B (C=CC(C)=O), catalyzed by an organoborane and an oxidant like hydrogen peroxide (H2O2) or sodium perborate (NaBO3). 2. Corey–Fuchs reaction to convert B (C=CC(C)=O) into C (C#CC(C)=C(C)O), using carbon tetrabromide (CBr4) and triphenylphosphine (PPh3) for alkyne synthesis. 3. Baeyer-Villiger oxidation of C (C#CC(C)=C(C)O) to form D (C#CCC(=O)[O-]), using peroxy acids like m-chloroperbenzoic acid (MCPBA) as an oxidizing agent to transform the alkene into an ester.

Step-by-step solution

Convert A to B

In this step, we will examine the transformation of A (C=CCCC=O) into B (C=CC(C)=O). The difference between the structures A and B is that one double bond in A is reduced and a methyl group (CH3) is added to the conjugated carbon of the double bond. This suggests that the reaction involved may be a hydrometalation-oxidation sequence that used a reducing agent and an oxidant, like organoboranes (such as 9-borabicyclo[3.3.1]nonane) or diborane, in combination with an oxidant like hydrogen peroxide (H2O2) or sodium perborate (NaBO3), to modify the double bond positions in A.

Convert B to C

In this step, we will examine the transformation of B (C=CC(C)=O) into C (C#CC(C)=C(C)O). The difference between the structures B and C is the conversion of a single bond (C-C) into a triple bond (C≡C). This suggests that the reaction involved may be an alkyne synthesis reaction, such as the Corey–Fuchs reaction using carbon tetrabromide (CBr4) and triphenylphosphine (PPh3) for the conversion.

Convert C to D

Lastly, we will examine the transformation of C (C#CC(C)=C(C)O) into D (C#CCC(=O)[O-]). The difference between the structures C and D is the conversion of a double bond (C=C) into a carbonyl group (C=O) along with a change in the structure of the attached oxygen atom. This suggests that the reaction involved may be an oxidation reaction, such as the Baeyer-Villiger oxidation using peroxy acids as the oxidizing agent (like m-chloroperbenzoic acid, MCPBA) to transform the alkene into an ester. In summary, the reaction sequence transforming compound A into compound D involves a series of reagents and reaction conditions that help perform hydroboration-oxidation, alkyne synthesis, and Baeyer-Villiger oxidation reactions respectively.