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Updated: Nov 1, 2025

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Switching between mono and doubly reduced odd alternant hydrocarbon: designing a redox catalyst
Jasimuddin Ahmed1, Paramita Datta1, Arpan Das1
1Department of Chemical Sciences, Indian Institute of Science Education and Research-Kolkata Mohanpur-741246 India swadhin.mandal@iiserkol.ac.in.
Abstract:
Since the early Hückel molecular orbital (HMO) calculations in 1950, it has been well known that the odd alternant hydrocarbon (OAH), the phenalenyl (PLY) system, can exist in three redox states: closed shell cation (12π e-), mono-reduced open shell neutral radical (13π e-) and doubly reduced closed shell anion (14π e-). Switching from one redox state of PLY to another leads to a slight structural change owing to its low energy of disproportionation making the electron addition or removal process facile. To date, mono-reduced PLY based radicals have been extensively studied. However, the reactivity and application of doubly reduced PLY species have not been explored so far. In this work, we report the synthesis of the doubly reduced PLY species (14π e-) and its application towards the development of redox catalysis via switching with the mono-reduced form (13π e-) for aryl halide activation and functionalization under transition metal free conditions without any external stimuli such as heat, light or cathodic current supply.
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