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Updated: Nov 16, 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
A continuous flow synthesis of [1.1.1]propellane and bicyclo[1.1.1]pentane derivatives
Kian Donnelly1, Marcus Baumann1
1School of Chemistry, University College Dublin, Science Centre South, Belfield, D04 N2E2, Ireland. marcus.baumann@ucd.ie.
Abstract:
A continuous flow process to generate [1.1.1]propellane on demand is presented rendering solutions of [1.1.1]propellane that can directly be derivatised into various bicyclo[1.1.1]pentane (BCP) species. This was realised in throughputs up to 8.5 mmol h-1 providing an attractive and straightforward access to gram quantities of selected BCP building blocks. Lastly, a continuous photochemical transformation of [1.1.1]propellane into valuable BCPs bearing mixed ester/acyl chloride moieties was developed.
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