Hydroboration-Oxidation

Key Concepts

• Hydroboration-Oxidation: A two-step reaction that adds water (H and OH) to an alkene.
• Anti-Markovnikov Hydration: In this reaction, the hydroxyl group (OH) is added to the less substituted carbon of the alkene.
• Syn Addition: Both hydrogen (H) and hydroxyl (OH) are added to the same side of the alkene.

Steps of the Reaction

1. Hydroboration:
   • Involves the addition of borane (BH3) to the alkene.
   • The reaction proceeds with the hydrogen atom from BH3 preferentially adding to the more substituted carbon, while the boron attaches to the less substituted carbon.
   • This step results in the formation of a trialkylborane intermediate.
2. Oxidation:
   • The trialkylborane is treated with hydrogen peroxide (H2O2) in a basic solution.
   • This step involves the rearrangement of the boron and the transfer of the hydroxyl group to the less substituted carbon, resulting in the final alcohol product.

Methodology

• Identify Conditions: Recognize the presence of BH3 and H2O2 as indicators of Hydroboration-Oxidation.
• Determine Regiochemistry: Place the OH group on the less substituted carbon (anti-Markovnikov).
• Assess Stereochemistry: Ensure that the addition is syn, meaning both groups are added from the same side.

Researchers/Sources Featured

• Professor Dave (the presenter of the video).