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Updated: Jul 8, 2026

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
A Brønsted acid mediated cascade enone synthesis from aldehydes containing a tethered propargylsilane
Rui Ramalho1, Peter J Jervis, Benson M Kariuki
1School of Chemistry, The University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Abstract:
MeSO3H effects the intramolecular allenylation of a series of aldehydes 1 to provide allenyl alcohol product 3 as a single diastereoisomer. Cyclization proceeds rapidly at -78 degrees C. However, when the reaction is performed at room temperature, aldehyde 1 provides enone product 7 instead. A mechanism for the formation of this product is proposed in which the initially formed allenyl alcohol 3 undergoes dehydration to provide an allyl carbocation, which is trapped with water, thereby installing the enone.
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