Iron-Catalyzed Cycloisomerization and C-C Bond Activation to Access Non-canonical Tricyclic Cyclobutanes
Related Experiment Video
Updated: Sep 5, 2025

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
Frederik Kramm1, Franziska Ullwer1, Benedict Klinnert2
1Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
Abstract:
Cycloisomerizations are powerful skeletal rearrangements that allow the construction of complex molecular architectures in an atom-economic way. We present here an unusual type of cyclopropyl enyne cycloisomerization that couples the process of a cycloisomerization with the activation of a C-C bond in cyclopropanes. A set of substituted non-canonical tricyclic cyclobutanes were synthesized under mild conditions using [(Ph3 P)2 Fe(CO)(NO)]BF4 as catalyst in good to excellent yields with high levels of stereocontrol.
Related Concept Videos
Cycloaddition Reactions: MO Requirements for Thermal Activation
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Cycloaddition Reactions: Overview
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Thermal and Photochemical Electrocyclic Reactions: Overview
![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)
