Structural and electrochemical properties of a novel N,N′-dialkyl-substituted quinone diimine

Abstract

trans,trans-3,3,7,7,10,10,14,14-Octamethyl-1,2,3,4,4a,7,7a,8,9,10,11,11a,14,14a-tetradecahydroquino[2,3-b]acridine 5, formed by a Lewis acid-catalyzed biscyclization of N-arylbisimine 3 and subsequent autoxidation, represents the first stable example of the unexplored class of N,N′-dialkyl-substituted quinone diimines. The X-ray crystal structure of 5 exhibits the following features: space group P2₁/c; a ribbon-like arrangement of two parallel strands along the b-axis. The smallest intermolecular distance between two quinoid systems is 4.846 Å and therefore any close aromatic contacts in this material can be precluded. A chemically reversible single electron reduction at E⁰ = –1.87 V has been observed by cyclic voltammetry.

References

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