Related Experiment Video
Updated: Jul 19, 2026

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
Total synthesis of the hydroxyketone kurasoin A using asymmetric phase-transfer alkylation
Merritt B Andrus1, Erik J Hicken, Jeffrey C Stephens
1Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, Utah 84602-5700, USA. mbandrus@chem.byu.edu
Abstract:
The total synthesis of the farnesyltransferase inhibitor kurasoin A has been achieved using a novel asymmetric phase-transfer-catalyzed glycolate alkylation reaction. 2,5-Dimethoxyacetophenone 7 with cinchonidinium catalyst 9(10 mol %) and hydroxide base with pivaloyl benzyl bromide 8 provided S-alkylation product 10 in high yield (80-99%) and excellent enantioselectivity. Baeyer-Villiger oxidation, Weinreb amide formation, and benzyl Grignard addition to the TES-ether 17 gave the protected target. Lithium hydroxide and peroxide generated kurasoin A ([alpha](D) +8.4 degrees ) without isomerization.
Related Concept Videos
Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis
α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
Aldol Condensation with β-Diesters: Knoevenagel Condensation

