Preparation and Optical and Electrochemical Properties of Phthalocyanines with Four or Eight Diphenylphosphino, Diphenylphosphoryl, and Diphenylthiophosphinyl Groups

Abstract

Several phthalocyanines (Pcs), in which four or eight phosphines are directly linked to their periphery, have been prepared. The starting materials, 4‐(diphenylphosphino)‐5‐chlorophthalonitrile (2), 4,5‐bis(diphenylphosphino)phthalonitrile (3), and 4‐(diphenylphosphino)‐5‐(diphenylphosphoryl)‐phthalonitrile (4), were prepared by the reaction of 4,5‐dichlorophthalonitrile (1) and diphenyltrimethylsilylphosphine in toluene at 110 °C. Compound 2 was treated with Li in hexan‐1‐ol at 120 °C, to produce β‐tetrakis(diphenylphosphino)tetrachloroPc [Pc(PPh2)4Cl4, 11], while refluxing 3 in ethoxyethanol in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) yielded β‐octakis(diphenylphosphino)Pc [Pc(PPh2)8, 12]. The reactions of 11 with mCPBA or elemental sulfur produced β‐tetrakis(diphenylphosphoryl)tetrachloroPc [Pc(POPh2)4Cl4, 13] or β‐tetrakis(diphenylthiophosphinyl)tetrachloroPc [Pc(PSPh2)4Cl4, 15], respectively, whereas that of 12 with mCPBA or elemental sulfur afforded β‐octakis(diphenylphosphoryl)Pc [Pc(POPh2)8, 14] or β‐octakis(diphenylthiophosphinyl)Pc [Pc(PSPh2)8, 16], respectively. β‐Octakis(diphenylphosphino)‐α‐octafluorophthalocyaninato magnesium [Pc(PPh2)8F8Mg, 17] was prepared from tetrafluorophthalonitrile (6) in two‐step reactions. The structures of simplified model compounds 11a–16a were optimized using DFT methods with the Gaussian 09 program. The optimized structures were utilized to calculate the HOMO and LUMO orbital energies, and the electronic transitions in the absorption spectra by the TD‐DFT method.

Dye‐sensitized solar cells based on zinc(II) phthalocyanines bearing 3‐pyridin‐3‐ylpropoxy anchoring groups

“…[ 12 ] Compared with the peripheral nonchlorinated complex, the slight blue shift of the λ max for the peripheral chlorinated complex can be ascribed to the electron‐withdrawing effect of the chlorine atoms, which is consistent with previous studies. [ 13,14 ] The spectra of the dyes adsorbed onto TiO 2 film show obviously red‐shifted Q bands as well as new bands around 640 nm, indicating the formation of H‐aggregates, [ 15 ] when compared with the corresponding solution spectra. The red‐shifted Q bands might be due to the interaction between the anchoring group of the dye and the TiO 2 surface.…”

Near-infrared absorbing π-extended hexadeca substituted phthalocyanines

“…The absorption at the Soret and Q band wavelengths can be fine-tuned by substitution of electron-withdrawing or donating groups [1,2,10,[13][14][15][16], by elongation of the π-conjugation system [17,18], or by introduction of central metals with one [19] or more axial ligands [20].…”

Nickel-catalyzed reductive coupling of nitroarenes and phosphine oxides to access phosphinic amides

“…Therefore, there is still a need for the synthesis of phosphinic amides using stable, simple, and readily available starting materials. 3 a ,5 Based on our ongoing studies on organic phosphorus, 6 we hypothesize that nitroarenes, which are widely used and stable chemicals (often as aniline precursors), can be reduced to azobenzenes under reductive conditions. These azobenzenes could then couple with phosphine oxides in the presence of transition metal catalysts to form phosphinic amides.…”