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In Woodward's landmark total synthesis of cholesterol, the compound that plagued the health of former President Bill Clinton, what type of chemical reaction using acetic acid was critical in removing the C₂O alcohol substituent? Your answer
In Woodward's landmark total synthesis of cholesterol, the compound that plagued the health of former President Bill Clinton, what type of chemical reaction using acetic acid was critical in removing the C₂O alcohol substituent? Your answer O a. E₂
O b. SN₁
O c. Sn₂
O d. E₁
The type of chemical reaction using acetic acid was critical in removing the C₂O alcohol substituent is E₂The correct option is (a).In Woodward's landmark total synthesis of cholesterol, the critical chemical reaction for removing the C₂O alcohol substituent involved an E2 elimination reaction. This reaction is characterized by the elimination of two substituents, typically a proton (H⁺) and a leaving group (such as a halide ion), to form a double bond.1. E2 Elimination Reaction:- The E2 elimination reaction is a type of concerted elimination reaction where a proton and a leaving group are removed from adjacent carbon atoms to form a double bond.- This reaction typically occurs in one step without the formation of a carbocation intermediate.- The rate of E2 elimination is influenced by the strength of the base and the accessibility of the hydrogen to be removed.2. Role of Acetic Acid:- Acetic acid (CH₃COOH) can act as a weak acid, but it can also act as a source of acetate ion (CH₃COO⁻) in the presence of a stronger base.- In Woodward's synthesis, acetic acid likely acted as a solvent or co-solvent, providing a medium for the reaction to take place.3. Removal of C₂O Alcohol Substituent:- The C₂O alcohol substituent in cholesterol likely underwent elimination to form a double bond.- The reaction mechanism involved a base abstracting a proton from the adjacent carbon, while a leaving group (e.g., a sulfonate or a tosylate) departed.- This concerted process resulted in the formation of a double bond between the adjacent carbons, effectively removing the C₂O alcohol substituent.4. Reasoning for E2 Reaction:- The E2 elimination reaction is preferred when the substrate is unhindered and the leaving group is capable of forming a stable anion.- In Woodward's synthesis, the C₂O alcohol substituent was likely situated in a position conducive to E2 elimination, allowing for the efficient removal of the substituent to form the desired intermediate for further synthetic steps.In summary, Woodward's total synthesis of cholesterol likely involved an E2 elimination reaction facilitated by the presence of acetic acid, leading to the removal of the C₂O alcohol substituent and the formation of a key intermediate in the synthesis....