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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Rigidochromism of tetranuclear Cu(I)-pyrazolate macrocycles: steric crowding with trifluoromethyl groups
Shinaj K Rajagopal1, Matthias Zeller1, Sergei Savikhin2
1James and Margaret Tarpo Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA. alexwei@purdue.edu.
Abstract:
Macrocyclic Cu(I)-pyrazolate tetramers (Cu4pz4) can fold into compact structures with luminescent Cu4 cores whose emission wavelengths are sensitive to steric effects along the periphery of the macrocycle. Introducing CF3 at the C4 position of 3,5-di-Bu-pyrazolate increases steric crowding that modifies the conformational behavior of the Cu4pz4 complex, highlighted by a low-temperature martensitic transition. Variable-temperature analysis of solid-state luminescence reveal an unexpected blueshifting of emission with rising temperature.
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