Baker–Venkataraman rearrangement

The Baker - Venkataraman rearrangement is an intramolecular variant of the Allan -Robinson reaction. It is used for synthesis of substituted 1,3-diketone derivative of the phenol. The starting point is in this case of an acylated phenol derivative. The reaction is complete after their discoverers, the British chemist Wilson Baker - named Krishna Sami and Venkataraman (1900, 2002 ).

Mechanism

In the first step a base catalyzes the formation of an enolate. This takes intramolecularly to the carbonyl group of the phenol ester. In this case, a cyclic alkoxide is formed. This opens up to form a phenolate. In the last step the phenolate is protonated by acidic workup.

Use

The Baker - Venkataraman rearrangement is used as a key step for the synthesis of flavones and chromenes.

Pictures of Baker–Venkataraman rearrangement

Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement # Baker–Venkataraman rearrangement #
Base (chemistry) Enolate anion Digital Object Identifier Tetrahedron Letters
100500
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