Copper(ii) complexes of bis(aryl-imino)acenaphthene ligands: synthesis, structure, DFT studies and evaluation in reverse ATRP of styreneElectronic supplementary information (ESI) available: Figures containing the mass spectra of compounds 1-3 and the corresponding simulations (Fig. S1-S4), the 1H NMR spectra of complexes 1 and 2 (Fig. S5), the cyclic voltammograms of complexes 1, 2 and 3 (Fig. S6 and S7), and 1H and 13C{1H} NMR spectra of a polystyrene sample (Fig. S8-S10); tables containing pol

• Main Authors: Fliedel, Christophe, Rosa, Vitor, Santos, Carla I. M, Gonzalez, Pablo J, Almeida, Rui M, Gomes, Clara S. B, Gomes, Pedro T, Lemos, M. Amélia N. D. A, Aullón, Gabriel, Welter, Richard, Avilés, Teresa
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c4dt01069h

Two new Ar-BIAN Cu( ii ) complexes (where Ar-BIAN = bis(aryl-imino)acenaphthene) of formulations [CuCl 2 (Mes-BIAN)] ( 1 ) (Mes = 2,4,6-Me 3 C 6 H 2 ) and [CuCl 2 (Dipp-BIAN)] ( 2 ) (Dipp = 2,6-iPr 2 C 6 H 3 ) were synthesised by direct reaction of CuCl 2 suspended in dichloromethane with the respective ligands Mes-BIAN ( L1 ) and Dipp-BIAN ( L2 ), dissolved in dichloromethane, under an argon atmosphere. Attempts to obtain these compounds by solubilising CuCl 2 in methanol and adding a dichloromethane solution of the corresponding ligand, under aerobic conditions, gave also compound 1 , but, in the case of L2 , the Cu( i ) dimer [CuCl(Dipp-BIAN)] 2 ( 3 ) was obtained instead of compound 2 . The compounds were fully characterised by elemental analyses, MALDI-TOF mass spectrometry, FT-IR, 1 H NMR and EPR spectroscopic techniques. The solid-state molecular structures of compounds 1-3 were determined by single crystal X-ray diffraction, showing the expected chelation of the Ar-BIAN ligands and two chloride ligands completing the coordination sphere of the Cu( ii ) centre. In the case of the complex 1 , an intermediate coordination geometry around the Cu( ii ) centre, between square planar and tetrahedral, was revealed, while the complex 2 showed an almost square planar geometry. The structural differences and evaluation of energetic changes were rationalised by DFT calculations. Analysis of the electrochemical behaviour of complexes 1-3 was performed by cyclic voltammetry and the experimental redox potentials for Cu( ii )/Cu( i ) pairs have been compared with theoretical values calculated by DFT in the gas phase and in dichloromethane and methanol solutions. The complex 1 exhibited good activity in the reverse atom transfer radical polymerisation (ATRP) of styrene. [CuCl 2 (Ar-BIAN)] complexes are synthesised and characterised, showing MeOH/O 2 driven reduction to [CuCl(Ar-BIAN)] 2 , and are evaluated in reverse ATRP of styrene.