Brook rearrangement

The Brook rearrangement is a significant chemical reaction in organic chemistry, involving the migration of an alkoxy group within a molecule. This rearrangement is named after the Canadian chemist Adrian Gibbs Brook, who first reported the reaction in the 1950s. The Brook rearrangement is particularly notable for its application in the synthesis of complex organic molecules, including natural products and pharmaceuticals.

Mechanism

The Brook rearrangement involves the migration of an alkoxy group from a silicon atom to an adjacent carbon atom. This process is typically facilitated by the presence of a base. The reaction mechanism begins with the deprotonation of the alkoxy group, leading to the formation of a siliconate intermediate. Subsequently, the alkoxy group migrates from the silicon to the adjacent carbon atom, resulting in the formation of a new carbon-oxygen bond.

Applications

The Brook rearrangement has found widespread application in organic synthesis, particularly in the construction of complex molecular architectures. It is utilized in the synthesis of lactones, ketones, and esters, among other compounds. The ability to manipulate the position of alkoxy groups within a molecule makes the Brook rearrangement a valuable tool for organic chemists.

Variants

Several variants of the Brook rearrangement exist, each tailored to specific synthetic requirements. These include the intramolecular Brook rearrangement, which occurs within a single molecule, and the intermolecular Brook rearrangement, where the alkoxy group migrates between two different molecules. Additionally, asymmetric versions of the Brook rearrangement have been developed, allowing for the enantioselective synthesis of chiral molecules.

See also

• Organosilicon chemistry
• Rearrangement reaction
• Organic synthesis