Complexes of ferrous phthalocyanine with aromatic nitroso compounds, isocyanides, and phosphites

Abstract

A number of new adducts of ferrous phthalocyanine (FePc) have been isolated. These include mixed-ligand complexes LFePcL' [I-= a nitroso aromatic group, L' = n-butylamine or N-methylimidazole; L = cyclohexyl isocyanide, L' = N-methylimidazole; L = a phosphite, L' = n-butyiamine] and bis adducts LzFePc [where L is an isocyanide or a phosphite], The complexes have been characterized by elemental analysis, electronic spectra, infrared spectra, and proton magnetic resonance spectra. The ring-current-induced shifts found for coordinated nitrosobenzene have been analyzed and it is concluded that this ligand coordinates iron through the nitrogen lone pair. The rate of exchange between free and complexed nitrosotoluene in ( C H~C~H~N O ) F~P C (~-C~H~N H Z ) has been determined by observing the 'H NMR spectrum under intermediate exchange conditions. The exchange occurs via a dissociative path and the activation parameters for exchange are AH* = 20.1 f 0.2 kcal/mol and AS* = 14.2 * 0.2 eu.

Octahedral iron(ii) phthalocyanine complexes: multinuclear NMR and relevance as NO2 chemical sensors

“…In the first of these, the 1 H, 13 C gHMQC spectra showed no cross-peak between the lowest frequency resonance (d H = -4 to -7 ppm) with any carbon signal. And further, the 1 H, 15 N gHMQC spectra, shown in Fig. 1, correlate these low frequency NH 2 signals to their respective nitrogen-15 resonances with clear one bond couplings between both nuclei.…”

“…Inspired by the work of Watkins and Balch in the 70's, 15 where a number of bis adducts and mixed-ligand ferrous phthalocyanine were isolated, we decided to extend the variety of these two families of compounds and apply their attractive coordination properties of the iron metal on the field of sensors. As shown in Scheme 1, reaction of two equivalents of amine (decylamine, bencylamine, para-methoxybencylamine, or trimethylsilylmethylenamine) with FePc (1), in THF solution, affords complete conversion to the bisamine iron complexes, 2-5, respectively.…”

“…1, correlate these low frequency NH 2 signals to their respective nitrogen-15 resonances with clear one bond couplings between both nuclei. 15 N chemical shifts and coupling constants observed for the whole set of complexes are presented in Table 1.…”

“…In terms of structural information of FePc, apart from optical absorption and Mossbauer data, 30 spectroscopic data reported with respect to the coordination chemistry is scarce. 15,31 Only a few old reports shed light on 1 H NMR 17 and none of them are concerned about multinuclear NMR methodologies.…”

“…13 Some of us have already reported AlOOH nanostructured films doped with phthalocyaninato-iron(II) complexes, and tested their sensor abilities against CO and NO x . 14 In this paper we present the synthesis of some new iron(II) Pcbased coordination complexes, their structural characterization by multinuclear NMR ( 1 H, 13 C, 15 N, 31 P, 57 Fe), and their use as reactive, sensitive and cheap optical sensors for NO 2 determinations.…”