Dithioallyl cation (3 + 2) cycloadditions under aprotic reaction conditions: rapid access to spiro-fused cyclopentane
Frederick Degroote1, Bram Denoo1, Bram Ryckaert1
1OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium. johan.winne@ugent.be.
Abstract:
We report a general method to effect all-carbon (3 + 2) cycloadditions that can elaborate cyclopentenes from a range of olefins. The required dithioallyl cation reagents can be generated in a newly developed mild protocol starting from 2-allyloxypyridine precursors, thus avoiding the use of strong Brønsted acids. The novel method significantly expands the substrate scope, which now also includes acid-sensitive olefins, and thus enables the preparation of previously inaccessible spiro-fused scaffold types from simple and readily available starting materials.
Related Concept Videos
Cycloaddition Reactions: Overview
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Cycloaddition Reactions: MO Requirements for Thermal Activation
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Cycloaddition Reactions: MO Requirements for Photochemical Activation

![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
