Pyridinium Ylide-Mediated Diastereoselective Synthesis of Spirocyclopropanyl-pyrazolones via Cascade
Akanksha Kumari1, Dhirajkumar Jitendrabhai Patanvadiya1, Anshul Jain1
1Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan 342030, India.
Abstract:
We have devised a highly diastereoselective formal [2 + 1] annulation reaction of arylidene/alkylidine-pyrazolones with in situ-generated supported as well as standard pyridinium ylides to construct spirocyclopropanyl-pyrazolones. The cascade approach exhibits a wide range of functional group tolerance, gram-scale capability, and substrate versatility. A diverse range of spirocyclic cyclopropanes was synthesized extensively with both mediators, and the supported pyridine was reused in subsequent cycles. Density functional theory calculations confirmed the formation of spirocyclopropane as the lower energy pathway.
Related Concept Videos
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Cycloaddition Reactions: Overview
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Cycloaddition Reactions: MO Requirements for Thermal 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)
