Limits of delocalization in through-conjugated dinitrenes: aromatization or bond formation?

PR Serwinski, PM Lahti

Index: Serwinski, Paul R.; Lahti, Paul M. Organic Letters, 2003 , vol. 5, # 12 p. 2099 - 2102

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Citation Number: 49

Abstract

Dinitrenes 4 and 5 both can form quinonoidal structures by conjugative bond formation. However, ESR spectroscopy detects a thermally populated, excited-state, triplet quinonoidal structure only for 4, with a zero-field splitting of| D/hc|= 0.0822 cm-1,| E/hc|≌ 0.0 cm-1. The tendency to maintain aromaticity in the additional ring of 5 favors a dinitrene structure (with one less formal π-bond) over a quinonoidal structure. The thermally populated quintet ...