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Updated: Jun 6, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Harnessing Thermally Labile Tethered Tetraynes to Access para-Diethynylbenzenes: A Ni(0)-Catalyzed
Rajesh Chakrabortty1, Tamal Ballav1, Venkataraman Ganesh1
1Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721 302, India.
Abstract:
We disclose a Ni(0)-catalyzed [2 + 2 + 2] cocyclotrimerization of tethered tetraynes with alkynes, providing rapid access to para-diethynylbenzenes (p-DEBs), key scaffolds in optoelectronic materials, such as molecular wires, photovoltaics, and OLEDs. The method tolerates thermally labile tetraynes and delivers diverse p-DEBs. Control experiments supported the proposed mechanism. The synthetic utility was demonstrated by conversion to [5]-helicene, and the optical properties of p-DEBs were investigated.
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