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Hub AI
Chan rearrangement AI simulator
(@Chan rearrangement_simulator)
Hub AI
Chan rearrangement AI simulator
(@Chan rearrangement_simulator)
Chan rearrangement
The Chan rearrangement is a chemical reaction that involves rearranging an acyloxy acetate (1) in the presence of a strong base to a 2-hydroxy-3-keto-ester (2).[1]
This procedure was employed in the Holton Taxol total synthesis.[2]
The methylene bridge in the reactant with adjacent carbonyl and acetyl substituents is acidic and can be deprotonated by strong non-nucleophilic bases such as lithium tetramethylpiperidide or lithium diisopropylamide (LDA) as in an aldol reaction. The thus formed enolate then attacks the adjacent acetyl group through a short lived intermediate oxirane. Acidic workup liberates the free hydroxyl group.
Chan rearrangement
The Chan rearrangement is a chemical reaction that involves rearranging an acyloxy acetate (1) in the presence of a strong base to a 2-hydroxy-3-keto-ester (2).[1]
This procedure was employed in the Holton Taxol total synthesis.[2]
The methylene bridge in the reactant with adjacent carbonyl and acetyl substituents is acidic and can be deprotonated by strong non-nucleophilic bases such as lithium tetramethylpiperidide or lithium diisopropylamide (LDA) as in an aldol reaction. The thus formed enolate then attacks the adjacent acetyl group through a short lived intermediate oxirane. Acidic workup liberates the free hydroxyl group.