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Updated: Jul 19, 2026

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
pi-Conjugated conjoined double helicene via a sequence of three oxidative CC- and NN-homocouplings
Kouichi Shiraishi1, Andrzej Rajca, Maren Pink
1Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, USA.
Abstract:
Dimerization of planarized diamine 2 using benzoyl peroxide gave dihydrazine 1 in about 70% yield; that is, three dehydrogenations (one CC- and two NN-homocouplings) and two ring closures were attained in one synthetic step. Dihydrazine 1 may be viewed as a chiral pi-conjugated conjoined double helicene, with two homochiral [5]helicene-like fragments, annelated in their mid-sections. A relatively high barrier of approximately 35 kcal mol-1 for inversion of configuration for one of the [5]helicene-like helices in 1 was found.
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