Synthesis and Structure of Bis-Urea Phenazines

Abstract

Substituted phenazines 7 and 15 with two urea units have been prepared and characterized. X-ray structure analyses are reported for intermediates 5, 9, 11b and 12. According to theoretical calculations the geometry of the two urea moieties in phenazines 7 and 15 should be well suited for the binding of trigonal planar anions, such as nitrate. NMR titration revealed that compound 15 indeed shows a weak interaction with nitrate ions in DMSO.