The structures of two aldazines: 1,1′-(1E,1′E)- hydrazine-1,2-diylidenebis(methan-1-yl-1- ylidene)dinaphthalen-2-ol (Lumogen) and 2,2′- (1E,1′E)-hydrazine-1,2-diylidenebis(methan-1- yl-1-ylidene)diphenol (salicylaldazine) in the solid state and in solution

摘要

A combination of NMR spectroscopy and theoretical methods Density functional theory including dispersion corrections (DFT-D)udwas used to study the structures of Lumogen and salicylaldazine. In the solid state, Lumogen exists as the dihydroxy tautomer 1aud(an azine, C¼N–N¼C) as was already known from an X-ray determination. In a deuterated dimethyl sulfoxide solution, anotherudtautomer is observed besides 1a; its structure corresponds to the hydroxy-oxo tautomer 1b (a hydrazone, C¼N–NH–Csp2). In whatudconcerns salicylaldazine, we have observed only the dihydroxy tautomer 2a.