Ring Opening and Rearrangement of a Nitro-Capped Cobalt(III) Cage Complex With an N3S3 Donor Set

Abstract

Treatment of the N3S3 donor cage complex [Co(NO2-capten)]3+ (1-methyl-8-nitro-3,13,16-trithia-6,10,19-triazabicyclo[6.6.6]icosanecobalt(III)) with excess base leads to deprotonation of a secondary coordinated amine group, followed by loss of a methylene unit from the cap by a retro-Mannich type reaction. Subsequent intermolecular hydride transfer gives a novel oxidized and partly delocalized macrocyclic complexed carbanion (13-(4-amino-2-thiabutyl)-13-methyl-6-nitro-1,11-dithia-4,8-diazacyclotetradec-4-enato(6)cobalt(III)) that is stabilized by deprotonation, and which remains deprotonated even in strong acid.