Peripheral Palladium(II) and Platinum(II) Complexes of Bis(dimethylamino)porphyrazine

Abstract

The unsymmetrical porphyrazine (tetraazaporphyrin) bearing a single peripheral bis(dimethylamino) functionality, Mg[pz(NMe(2))(2)(Pr)(6)], was prepared by base-catalyzed cross condensation of dipropyl maleonitrile (in excess) with dimethylamino maleonitrile. The freebase (2H[pz(NMe(2))(2)(Pr)(6)]) and centrally metalated forms (M[pz(NMe(2))(2)(Pr)(6)]; M = Ni(II), Cu(II), Mn(III)) were prepared by treatment of Mg[pz(NMe(2))(2)(Pr)(6)] with trifluoroacetic acid and then the appropriate metal salt. PdCl(2) and PtCl(2) were coordinated to the peripheral bis(dimethylamino) chelates, yielding the bimetallic complexes, M[pz(NMe(2))(2)(Pr)(6)]M'Cl(2) (M = Ni, Cu; M' = Pd, Pt). The heteroleptic [N(2)-Pd-S(2)]-capped porphyrazines were prepared readily by substituting the chloride ions of M[pz(NMe(2))(2)(Pr)(6)]PdCl(2) with the dithiolene chelates, maleonitriledithiolate (mnt(2)(-)), benzenedithiolate (bdt(2)(-)), and 1,3-dithiole-2-one-4,5-dithiolate (dmid(2)(-)). The [N(2)-Pt-S(2)] complexes were prepared by reaction of M[pz(NMe(2))(2)(Pr)(6)]PtCl(2) with the dialkyltin-protected dithiolates dibutyltin(toluene-3,4-dithiolate) and dibutyltin(dmit). The peripheral heteroleptic [N(2)-M'-S(2)] core was found to be electroactive for electron-rich dithiolene ligands (bdt(2)(-), E(1/2)(Pd(III)/Pd(II)) = 0.22 V; tdt(2)(-), E(1/2)(Pt(III)/Pt(II)) = 0.20 V; dmid(2)(-), E(1/2)(Pd(III)/Pd(II)) = 0.19 V; dmit(2)(-), E(1/2)(Pt(III)/Pt(II)) = 0.19 V) but not for the relatively electron-poor dithiolene, maleonitriledithiolate (mnt(2)(-)). The X-ray structure of Ni[pz(NMe(2))(2)(Pr)(6)]Pd(mnt) (13) was determined. Crystal data for C(85)H(109)Cl(3)N(24)Ni(2)Pd(2)S(4): space group P2(1)/n; a = 17.435(4) Å, b = 17.982(2) Å, c = 30.577(2) Å; beta = 104.27(2) degrees; Z = 4.

Novel peripherally functionalized seco-porphyrazines: synthesis, characterization and spectroscopic evaluation

“…13 Thus, as an extension of this work, the synthesis of the more intriguing unsymmetrical 3:1 pzs bearing a single polyether amino-substituted pyrrole ring was undertaken. Due to the compatible rates of cyclization of dipropylmaleonitrile 6 and various aminomaleonitriles, 5 as the second agent for the crossed Linstead macrocyclizations. Dinitrile 4 has been previously synthesized, 15 while iodide 3 was obtained from commercially available tetra(ethylene)glycol 1 by mono-protection and conversion to the corresponding iodide 3.…”

Potential Aluminium(III)- and Gallium(III)-selective Optical Sensors Based on Porphyrazines

“…1a). [35][36][37] UV-Vis spectra were recorded on a Hitachi U-1900 spectrophotometer. UV-Vis monitored titrations were carried out in methanol- 38 The C hydrogen atoms were included in calculated positions with C-H = 0.93 -0.98 Å and refined as riding on their corresponding carbon atoms, with Uiso (H) = 1.2 Ueq (C) or 1.5 Ueq (methyl C).…”

Synthetic approaches to asymmetric phthalocyanines and their analogues

“…[268][269][270][271][272][273][274][275] For instance, asymmetric A 3 B type phthalocyanine analogues can easily form mono-or dinuclear phthalocyanine analogues 92-95 when reacted with the main-group or transition-metal ions ( Figure 6). Similarly, Ercolani and co-workers have shown that six out of eight available pyridine-type nitrogen atoms in symmetric phthalocyanine could be methylated using standard methylation agents.…”