Molecular recognition for stable organic radicals ? 2-(6-uradinyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxylElectronic supplementary information (ESI) available: synthesis details for 1 and 2; IR data; spin density computations for 2. See http://www.rsc.org/suppdata/cc/b3/b302901h/

Abstract

Stable radical 2-(6-uradinyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl shows antiferromagnetic spin pairing with 2J/k= -14 K, attributable to a close contact between unpaired spin density on the imidazole-type nitrogen atoms; hydrogen bonds aid dimer formation, but do not appear to play an eletronic role in the magnetic behaviour.