Towards N-alkylated phthalocyanines using 2,3,9,10,16,17,23,24-octaneopentoxyphthalocyanine

Abstract

<jats:p> 4,5-Dineopentoxyphthalonitrile was prepared from catechol and neopentyl tosylate in three steps. Condensation of this substituted phthalonitrile with lithium metal in 1-pentanol led to 2,3,9,10,16,17,23,24-octaneopentoxyphthalocyanine. Lithiation in tetrahydrofuran gave the dilithium phthalocyanine which on methylation did not give the expected N -methylated product 29,31-dimethylphthalocyanine. The precipitate formed on methylation appeared to be the N <jats:sup>+</jats:sup>- CH <jats:sub>3</jats:sub> derivative in which one of the peripheral nitrogens was N -methylated. Methylation with <jats:sup>13</jats:sup> CH <jats:sub>3</jats:sub> I likely yielded an N <jats:sup>+</jats:sup>-methylated phthalocyanine having the requisite increased mass in its mass spectrum. </jats:p>

Optical Spectra of Phthalocyanines and Related Compounds

“…3.27a). Reaction with strong Lewis acids, such as AlCl 3 [185] and TeCl 4 [90], as well as the alkylation of the meso nitrogen atom [186], gives rise to a similar spectral change. 3.2.3.2.…”

Revisiting the Ullman's Radical Chemistry for Phthalocyanine Derivatives

“…A 3 B‐type phthalocyanine classical synthetic methodology consists of the statistically crossover condensation of two appropriate phthalonitrile precursors in different ratio; in our case 4,5‐dineopentoxyphthalonitrile ( 2 ) and 4‐(5,5‐dimethyl‐1,3‐dioxane‐2‐yl)‐phthalonitrile ( 1 ). The synthesis of phthalonitrile 2 was carried out on the basis of Leznoff's procedure with substantial modifications (Scheme S1 in the Supporting Information). Catechol was brominated first, in which1,2‐dibromo‐4,5‐dihydroxybenzene was treated with hexamethylphosphoramide, KOH, tetraheptylammonium bromide, and neopentyl tosylate to give 1,2‐dibromo‐4,5‐dineopentoxybenzene.…”

“…4 and 10 show the typical split Qb and characteristico ff ree-based phthalocyanines. [20] In contrast, the low symmetry of 10 leads to closer Qb ands. Bb ands around 350 nm are almosti dentical to each other.N oteworthy is that the extension of the conjugation pathway introduced by the imino nitroxider adical moiety of 10 (l max = 441 nm) leads to a1 1nmr ed shift of the charge transfer band in comparison to that of 4 (l max = 430 nm).…”

“…4 and 10 were soluble in organic solvents such as DCM or THF in which the Beer-Lambert law was observed for both compounds in the range of 10 À6 m to 10 À5 m ( Figures S29-S33,S 54, S55 in the Supporting Information). [20] In contrast, the low symmetry of 10 leads to closer Qb ands. [20] In contrast, the low symmetry of 10 leads to closer Qb ands.…”

Synthesis and photophysical properties of novel phthalocyanine–perylenediimide–phthalocyanine triad and phthalocyanine–perylenediimide dyads

“…The rst phthalonitrile function group, 4,5-di-n-octyloxyphthalonitrile, was synthesized with three steps according to the previous literature. 20 The second phthalonitrile function group (compound 3) was prepared by combination of two intermediates (compound 1 and 2). 3-(2-Ethylhexyloxy)-6-hydroxyphthalonitrile 1 was synthesized from the controlled alkylation of 2,3-dicyano-1,4-dihydroquinone with 2-ethylhexylbromide in molar ratio of 1 : 1.…”