Related Experiment Video
Updated: Jun 5, 2025

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
Modular Synthesis of Dehydroprolines by an Energy-Transfer Enabled Cloke-Wilson Rearrangement
Austin D Marchese1, Tomislav Rovis1
1Department of Chemistry, Columbia University, New York, New York, 10027, United States.
Abstract:
A one-pot photocatalytic method is reported for the generation of dehydroprolines, valuable precursors to 5-aryl prolines. Imines, obtained via simple condensation of aminocyclopropane carboxylates (ACPC) with a broad range of aldehydes, were employed in this transformation without purification. We demonstrate this energy-transfer (EnT) enabled Cloke-Wilson-type rearrangement affords both the rare 1,2-dehydroprolines or the more thermodynamically favored 1,5-isomers with up to >20 : 1 selectivity in both directions, using an identical catalytic system from the same starting material. Syntheses of intermediates of bioactive molecules in high yields and selectivity highlight this enabling transformation. Mechanistic studies support the proposed triplet-triplet EnT mode of activation, distinct from the previously developed singlet excited states accessed via UV excitation.
Related Concept Videos
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Mechanism
Cycloaddition Reactions: Overview
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction
![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)
