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Updated: Jul 5, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Bis-[cyclic(alkyl)(amino)carbene]-derived diradicals
Mithilesh Kumar Nayak1, Benedict J Elvers2, Sakshi Mehta3
1Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500107, India. ajana@tifrh.res.in.
Abstract:
Crystalline polymeric structures of trans-1,4-cyclohexylene bridged N-tethered bis-CAACs in the form of their LiOTf adducts were synthesized and isolated. These were further used as building blocks for the synthesis of crystalline (amino)(carboxy)-based diradicals. The triplet diradical character of these compounds was unambiguously confirmed by the presence of a half-field signal in their EPR spectra. Theoretical calculations show that the singlet state is marginally more stable than the triplet state.
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