Ch. 16 - Reactions of Aldehydes and Ketones • More Reactions of Carboxylic Acid Derivatives

Bruice8th EditionOrganic ChemistryISBN: 9780135213711당신이 사용하는 게 아니라요?교과서 변경

Bruice 8th Edition

Ch. 16 - Reactions of Aldehydes and Ketones • More Reactions of Carboxylic Acid Derivatives

문제 90

16장, 문제 90

Identify compounds A and B:

검증된 단계별 안내

Step 1: Analyze the first reaction. The compound X reacts with a Gilman reagent (R2CuLi), which is known for performing conjugate addition to α,β-unsaturated carbonyl compounds. This suggests that X is likely an α,β-unsaturated ketone or aldehyde.

Step 2: The Gilman reagent adds one of its alkyl groups to the β-carbon of the α,β-unsaturated system in X. This results in compound Y, which is a substituted ketone or aldehyde. The reaction is followed by acidic workup (H3O+), ensuring the stability of the product.

Step 3: Analyze the second reaction. Compound Y reacts with an organometallic reagent, specifically a Grignard reagent (R-MgBr). Grignard reagents typically add to the carbonyl group of ketones or aldehydes, forming an alcohol after acidic workup.

Step 4: The Grignard reagent adds its alkyl group to the carbonyl carbon of Y, forming a tertiary alcohol after the acidic workup. The final product is a tertiary alcohol with a cyclohexane ring and multiple substituents.

Step 5: Based on the structure of the final product provided in the image, deduce the structures of compounds X and Y by working backward. Compound X is likely an α,β-unsaturated ketone, and compound Y is the intermediate ketone formed after the conjugate addition of the Gilman reagent.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Grignard Reagents

Grignard reagents are organomagnesium compounds, typically represented as R-MgX, where R is an organic group and X is a halogen. They are highly reactive and serve as nucleophiles in organic synthesis, allowing for the formation of carbon-carbon bonds. In the reaction shown, a Grignard reagent (MgBr) is used to add to a carbonyl compound, facilitating the formation of alcohols.

Organocuprates

Organocuprates, or Gilman reagents, are organometallic compounds containing copper, typically represented as R2CuLi. They are less reactive than Grignard reagents and are used for selective carbon-carbon bond formation. In the reaction depicted, an organocuprate is employed to react with compound X, leading to the formation of compound Y through a nucleophilic addition.

Acid Workup

An acid workup is a common step in organic synthesis that involves the addition of an acid, such as H3O+, to neutralize basic reaction conditions and protonate intermediates. This step is crucial for converting reactive intermediates into stable products, such as alcohols. In the provided reaction scheme, the acid workup is essential for converting the Grignard and organocuprate reactions into the final alcohol products.