Distortional Isomerism in Copper(II) Nitrato Complexes of N,N′,N″‐Tris{[(para‐nitrobenzyl)phenyl]aminoethyl}amine

Abstract

The tris(aminoethyl)amine derivative tris{ [(para-nitrobenzyl)phenyl]aminoethyl}amine [(p-NO 2 BP) 3 tren] was reacted with copper(II) nitrate in thf to yield three different solvates of [Cu(p-NO 2 BP) 3 trenNO 3 ]NO 3 (C1) in the solid state, namely α-C1·2thf (C2), β-C1·2.5thf (C3) and α-C1·(thf) 1.5 · (iPr 2 O) 0.25 (C4). The light green-yellow coloured complexes, C2 and C4, are different solvates of the one distortion isomer, while the dark-green C3 is a different distortion isomer. The spectral properties of these distortion isomers were examined, and the structures of C3 and C4 were determined by Xray crystallography. The difference in the physical properties (EPR and reflectance electronic spectra) of the light and dark

Proton and Electron Transfer to a Polymer‐Supported Nitrido Molybdenum(VI) Complex

“…The EPR spectrum of P-5b is less well resolved (g 1,2,3 = 2.058, 2.134, and 2.250; A 1,2,3 = 40, 20, and 170 G), but it is characteristic of Cu II coordination. These values are similar to the data reported for comparable copper(II) complexes with substituted tren ligands [52,54] under dilute conditions. This suggests that tridentate coordination sites are indeed available on the matrix for metal-ion coordination and that the coordination sites are magnetically isolated.…”

“…As further proof for the correct ligand formation on the polymeric support, we introduced Cu II as an optical probe and EPR label49–51 by treating P‐1 with Cu(ClO 4 ) 2 · 6H 2 O and Cu(NO 3 ) 2 · 3H 2 O. Indeed, both Cu II ‐loaded resins P‐5a and P‐5b feature the green color of the immobilized Cu II complex and give broad absorptions between λ max = 700 and 900 nm in the diffuse reflectance UV/Vis (DR‐UV/Vis) spectra (Figure 5) similar to those of comparable copper(II) complexes 52. The perchlorate and nitrate counterions are detected by their characteristic stretching vibrations at 1105 and 1384 cm –1 , respectively.…”

“…Indeed, both Cu II -loaded resins P-5a and P-5b feature the green color of the immobilized Cu II complex and give broad absorptions between λ max = 700 and 900 nm in the diffuse reflectance UV/Vis (DR-UV/Vis) spectra ( Figure 5) similar to those of comparable copper(II) complexes. [52] The perchlorate and nitrate counterions are detected by their characteristic stretching vibrations at 1105 and 1384 cm -1 , respectively. The amount of immobilized copper in P-5b matches the expected value as measured by inductively coupled plasma MS (ICP-MS; 0.46 mmol g -1 ).…”