Preparation and Electrochemical and Optical Properties of Unsymmetrically Substituted Phthalocyanines with One or Two Trithiole Rings and Related Symmetric Derivatives

Abstract

4,5-Bis(benzylthio)-3,6-diethylphthalonitrile (1) was mixed with 4 -t-butylphthalonitrile and then treated with lithium alkoxide in n-hexanol to produce the corresponding unsymmetrically substituted phthalocyanines (2) and (3) with two or four benzylthio groups, respectively. Treatment of phthalocyanine (2) with nickel(II) acetate yielded the corresponding metal complex 2-Ni. Two benzyl groups of 2 and 2-Ni were removed with lithium/THF/ammonia at -78 degrees C under argon, and the dithiolate anions generated were then reacted with elemental sulfur to give monotrithiolophthalocyanines (5) and (5-Ni). A similar treatment of 3 produced bistrithiolophthalocyanine (6). Tetrakistrithiolophthalocyanine (7-Ni) was prepared by complexation of phthalocyanine (4) with nickel(II) acetate, followed by a Birch reduction of the resulting nickel(II) complex (4-Ni), and then sulfurization and cyclization of the octathiolate anions that were generated. The structures of the phthalocyanines were determined by (1)H NMR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The optical and electrochemical properties of the phthalocyanines were examined by UV-vis absorption spectroscopy and cyclic voltammetry. Treatment of 5, 5-Ni, 6, 7, and 7-Ni with trifluoroacetic acid in chloroform generated positively charged species, which were characterized by UV-vis and/or NMR spectroscopy.

Asymmetric phthalocyanine derivatives containing 4-carboxyphenyl substituents for dye-sensitized solar cells

“…In the literature, three methods have been commonly used for the synthesis of unsymmetrical phthalocyanines: a statistical condensation [21], a polymer support [22] or using subphthalocyanines [23]. Among these methods, the statistical cyclotetramerization was used to prepare the phthalocyanines in this study.…”

Preparation and optical and electrochemical properties of octaethylphthalocyanines fused with several tetrathiafulvalene units

“…As starting compounds, 4,5-xylylenedithio-3,6-diethylphthalonitrile (1a) and 4,5-bis(benzylthio)-3,6-diethylphthalonitrile (1b) were prepared from 1,4-diethyltetrabromobenzene via several step reactions by the procedure reported previously [6,7]. Compound 1a was treated with AlCl 3 in toluene at room temperature and then with carbonyldiimidazole or thiocarbonyldiimidazole at reflux temperature, which gave benzo-1,3-dithiole-2-one (2-O) and benzo-1,3-dithiole-2-thione (2-S) in 79% and 61% yields, respectively (Scheme 1).…”

“…• C to produce hexakis (benzylthio)mono(tetrathiafulvaleno)phthalocyanine (5), tetrakis(benzylthio)bis(tetrathiafulvaleno)phthalocyanine (6), and bis(benzylthio)tris(tetrathiafulvaleno)phthalocyanine (7). The structures of 5, 6, and 7 were determined by 1 …”

“…As a related study, we recently reported the preparation of octakis(benzylthio)phthalocyanine [PcSBn] and its selenium derivative [6]. Furthermore, tetrakis(trithiolo)phthalocyanines and double-decker phthalocyanine were prepared from tetrakis(o-xylylenedithio)phthalocyanines and octakis(methylthio)phthalocyaninato titanium (IV) oxide, respectively [7].…”

Synthesis, characterization, fluorescence spectra and energy transfer properties of a novel unsymmetrical zinc phthalocyanine with peripherally coordinated Ru(II) complex

“…In the literature, three methods have been commonly used for the synthesis of unsymmetrical phthalocyanines: a statistical condensation method [30], a polymer support method [31] or using subphthalocyanines [32]. Among these methods, the statistical cyclotetramerization was used to prepare the phthalocyanines in this study.…”