Chemical reactivity in monolayers: study of an amphiphilic tetrapyridinoporphyrazine in Langmuir-Blodgett films

Synthesis, electrochemical and spectroelectrochemical studies of metal-free 2,9,16,23-tetraferrocenylphthalocyanine

“…Preparatian of 1 -( 3, 4-frcy arnp luny I ) ferrocene ( 4 ) Using a method previously described for the preparation of phenylferrocene [28], ferricenium chloride (2) reacted with 4-diazoniumphthalonitrile bisulfate (3) [29] to give 1-(3,4-dicyanophenylXerrocene (4). Compound (4) was thus prepared by dissolving ferrocene (3.3 g, 0.017 mol) in anhydrous diethyl ether (30 mL), followed by oxidation by the addition of ferric chloride/ diethyl ether. The reaction was stirred for 30 min and then extracted with water until all the ferricenium chloride (2) had been removed.…”

Photophysical Properties of Neutral and Cationic Tetrapyridinoporphyrazines

“…However, while the absorption Q band of 2,3-TPyPzs is blue-shifted in relation to that of phthalocyanines by 30-40 nm, which is undesirable for PDT purposes, that of 3,4-TPyPzs remains at the same position as phthalocyanines. Moreover, 3,4-TPyPzs undergo quaternization easier than 2,3-TPyPzs, which has made possible to obtain several cationic 3,4-TPyPz soluble in organic solvents (14)(15)(16)(17). Nevertheless, to the best of our knowledge the only water soluble 3,4-TPyPzs reported to date are the methylated copper and cobalt derivatives (9,12).…”

Two-Dimensional Crystallization of Phthalocyanine Pigments at the Air/Water Interface

“…As a means of studying and controlling these characteristics, Langmuir and Langmuir-Blodgett (L-B) monolayer techniques have been used extensively to form ordered molecular assemblies of Pc's [11][12][13][14][15] and porphyrins. 16,17 Nearly all of these investigations have involved pigments prederivatized with long alkyl chains (so as to introduce amphiphilic character to the film); yet despite the excellent film-forming properties of many of these derivatives, evidence indicates that none of these approaches has been able to eliminate their strong cofacial interactions.…”

“…This model, with a tilted complex along one of the diagonals, yields a distortion of the 2 × 2 superlattice, creating a centered rectangular lattice with two complexes per unit cell. The Bragg reflection at Q⊥ ) 0.226 Å -1 displayed in Figure2is due to the(11) or the equivalent (1,1 h) Bragg reflection from the superlattice. (b) A side view of the staggered boxes (representing the complexes) along the diagonal (viewed parallel to the x axis).…”