Ni(II) complexes with (AE)-trans-N,N 0 -bis(salicylidene)-1,2-cyclohexanediamine ([Ni(salcn)]), and its methyl ([Ni(salcn(Me))]) and tert-butyl ([Ni(salcn(Bu))]) derivatives have been synthesized. Anodic electropolymerization has been used to form electrodes modified by polymer films. FTIR and FTIR ATR methods showed that the obtained films consist of polymers of phenyl-phenyl type. The structure of poly[Ni(salcn)] is built with 1,2,4-and 1,2,3,5-substituted chains. A three-step process of the oxidation of the complexes and their films has been ascertained on the basis of cyclic voltammetry measurements.Furthermore we have also detected the oxidized species which probably serve as intermediates for polymer formation. The influence of the substituent in the phenolate moiety on the type of reaction after which the dimerization and polymerization reaction occurs has been evidenced. Furthermore the substituent dependence on the stability of the phenoxyl radical complex and the Ni(II)-phenoxonium cation has been noticed. For the [Ni(salcn(Bu))] complex, an additional electropolymerization step -the adsorption of the reagent on the electrode surface -has been observed. † Electronic supplementary information (ESI) available: Table S1. Comparison of the FTIR ATR bands of poly[Ni(salcn)] films (electrosynthesized in Bu 4 NPF 6 or Bu 4 NClO 4 ) with the FTIR bands of the [Ni(salcn)] complex; Fig. S1. Cyclic voltammograms of complexes in TBAH/CH 2 Cl 2 , 0.1-1.6 V, v = 0.05 V s À1 , 1st scans vs. Ag/AgCl and Fig. S2. Cyclic voltammograms of complexes in TBAH/CH 2 Cl 2 , 0.1-2.1 V, v = 0.05 V s À1 , 1st scans vs. Ag/AgCl. See

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This work concerns the investigation of stability constants of silver(I) ions with the tetrapyrrolidinyl-PNP-lariat ether L1 in acetonitrile solution and tetramorpholinyl-PNP-lariat ether L2 in acetonitrile and methanol solutions. The new tetramorpholinyl-PNP-lariat ether L2 was synthesized on the basis of the procedure described in a previous publication. Stability constants of complexes with silver ions were determined using a simple potentiometric titration. Furthermore, NMR spectra were obtained to investigate how the complexation of silver(I) ions by the investigated macrocyclic ligand occurs. Spectrometric data analyses and potentiometric measurements indicate that complexation of Ag + involves participation of the endocyclic nitrogen atom of the cyclophosphazene ring and polyether oxygen donors. As regards L1 the stability of the obtained complex is influenced by pyrrolidinyl groups. On the other hand, L2 includes the morpholinyl subunits attached to the exocyclic P atom, having in their structure the oxygen atom, which pulls out the electrons of the cyclophosphazene ring and thereby destabilizes the formation of a coordination system.

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