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Updated: Nov 25, 2025

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Flow Technology for Telescoped Generation, Lithiation and Electrophilic (C3 ) Functionalization of Highly Strained
Pantaleo Musci1, Timo von Keutz2,3, Ferdinand Belaj2
1Flow Chemistry and Microreactor Technology FLAME-Lab, Department of Pharmacy-Drug Sciences, University of Bari "A. Moro", Via E. Orabona 4, 70125, Bari, Italy.
Abstract:
Strained compounds are privileged moieties in modern synthesis. In this context, 1-azabicyclo[1.1.0]butanes are appealing structural motifs that can be employed as click reagents or precursors to azetidines. We herein report the first telescoped continuous flow protocol for the generation, lithiation, and electrophilic trapping of 1-azabicyclo[1.1.0]butanes. The flow method allows for exquisite control of the reaction parameters, and the process operates at higher temperatures and safer conditions with respect to batch mode. The efficiency of this intramolecular cyclization/C3-lithiation/electrophilic quenching flow sequence is documented with more than 20 examples.
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