Al-III phthalocyanines: Synthesis, properties, and crystal structure of tetra(n-butyl)-ammonium-trans-di(nitrito(O))phthalocyaninato(2-)aluminate(III)

[Al(Cl)Pc(2-)] reacts with excess ((n)Bu(4)N)NO2 in dimethylformamide yielding less soluble blue tetra(n-butyl)ammonium-trans-di (nitrito(O))phthalocyaninato(2-)aluminate(III), ((n)Bu(4)N)(trans)[Al(ONO)(2)Pc(2-)], which crystallizes in the monoclinic space group C2/c (No. 15) with Z = 4. The Al atom is in the special position 4d in the center of the Pc(2-) ligand and the two nitrit ions are monodentate O-coordinated in a mutually trans arrangement to the Al atom. The Al-O and average Al-N-iso bond distances are 1.927(2) and 1.956 Angstrom, respectively. The geometric data of the coordinated nitrite ion are: d(N-O) = 1.277(4) Angstrom; d(N-O) = 1.221(4) Angstrom; measured angle(O-N-O) = 114.3(3)degrees; measured angle(Al-O-N) = 121.3(2)degrees. The non-bonded O atoms are trans to the Al atom. The Pc(2-) ligand is slightly ruffled. The UV-VIS-NIR spectra and the vibrational spectra are discussed.