Show how to make these deuterium-labeled compounds, using CD₃MgBr and D₂O as your sources of deuterium, and any non-deuterated starting materials you wish.
b. CH₃C(OH)(CD₃)₂

Verified step by step guidance

1. Start with a non-deuterated ketone, such as acetone (CH3C(O)CH3), as your starting material. Acetone has a carbonyl group that can undergo nucleophilic addition reactions.
2. React acetone with CD3MgBr (a Grignard reagent containing deuterium). The nucleophilic CD3⁻ group will attack the electrophilic carbonyl carbon of acetone, forming a tetrahedral intermediate.
3. Protonate the tetrahedral intermediate by adding D2O (deuterium oxide). This step will replace the oxygen atom of the carbonyl group with an OD group, resulting in the formation of CH3C(OD)(CD3)2.
4. Recognize that the OD group can be converted to an OH group by exchanging the deuterium atom with a hydrogen atom. This can be achieved by treating the compound with a mild acidic or neutral aqueous solution.
5. The final product is CH3C(OH)(CD3)2, where the two CD3 groups are deuterium-labeled, and the hydroxyl group is non-deuterated.

Key Concepts

Deuterium Labeling

Deuterium labeling involves substituting hydrogen atoms in organic compounds with deuterium, a stable isotope of hydrogen. This process is crucial in tracing the pathways of chemical reactions and understanding molecular structures. In this context, deuterium-labeled compounds can provide insights into reaction mechanisms and kinetics.

Grignard Reagents

Grignard reagents, such as CD3MgBr, are organomagnesium compounds used in organic synthesis to form carbon-carbon bonds. They react with electrophiles, including carbonyl compounds, to create new carbon centers. Understanding how to utilize Grignard reagents is essential for constructing complex organic molecules, including those with deuterium labels.

Alcohol Formation

The formation of alcohols from carbonyl compounds is a fundamental reaction in organic chemistry. In this case, the reaction of a Grignard reagent with a carbonyl compound leads to the formation of a tertiary alcohol. Recognizing the mechanisms of alcohol formation, including the role of deuterium in the final product, is vital for synthesizing the desired deuterium-labeled compound.