Synthesis and characterization of a new fluorescent zwitterionic spirocyclic Meisenheimer complex of 1,3,5-trinitrobenzene

Abstract

In this communication we present the first stable zwitterionic spirocyclic Meisenheimer compound based on an N→N rearrangement in the reaction between picric acid and diisopropylcarbodiimide. The structure was confirmed by single-crystal X-ray diffraction. Furthermore, this compound exhibits interesting fluorescence properties (ψf = 0.4-0.5), not shared with a typical Meisenheimer complex, and a fluorescence lifetime (τ = 9.1 ns) in dichloromethane. © Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.