Related Experiment Video
Updated: Jun 16, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Synthesis of 2,6-disubstituted dihydropyrans via an efficient BiBr(3)-initiated three component, one-pot cascade
Robert J Hinkle1, Yajing Lian, Lee C Speight
1Department of Chemistry, the College of William & Mary, P. O. Box 8795, Williamsburg, VA 23187-8795, USA.
Abstract:
The rapid synthesis of cis-2,6-disubstituted dihydropyrans is achieved in a three-component, one-pot cascade reaction. BiBr(3)-ediated addition of ketene silyl acetals or silyl enol ethers to beta,gamma-unsaturated cis-4-trimethylsilyl-3-butenal provides a Mukaiyama aldol adduct containing a vinylsilane moiety tethered to a silyl ether. Addition of a second aldehyde initiates a domino sequence involving intermolecular addition followed by an intramolecular silyl-modified Sakurai (ISMS) reaction. Isolated yields of this one-pot reaction vary from 44 to 80% and all compounds were isolated as the cis-diastereomers (10 examples).
More Related Videos
14:11Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
08:56Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Related Concept Videos
Cycloaddition Reactions: Overview
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
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.
Radical Substitution: Allylic Bromination
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene