Phthalocyanine dyes synthesis

The present study reflects the re-design of a manufacturing process for the production of a copper phthalocyanine dye intermediate through a three step process involving synthesis, precipitation, and filtration. Figure 1 shows the reaction scheme for the original process. The sulfonation of copper phthalocyanine with chlorosulfonic acid is followed by a chlorination step with thionyl chloride that leads to the formation of the tetra-sulfonyl chloride dye intermediate. The product is isolated via a water precipitation (quenching) from the acidic solution followed by a filtration operation. 

Salih Agirtas, M., MetinQelebi, Sel9ukGumus. (2013). New water soluble phenoxy phenyl diazenyl benzoic acid substituted phthalocyanine derivatives Synthesis, antioxidant activities, atypical aggregation behavior and electronic properties. Dyes and Pigments 99, 423 31. 

Phthalocyanines. Phthalocyanine is the only novel chromogen of commercial importance discovered siace the nineteenth century. It was discovered accidendy ia 1928, when duriag the routine manufacture of phthalimide from phthaUc anhydride and ammonia it was found that the product contained a blue contaminant. Chemists of Scottish Dyes Ltd, now part of Zeneca, carried out an iadependent synthesis of the blue material by passiag ammonia gas iato molten phthaUc anhydride containing iron filings. The importance of the colorant was realized (it was iatensely colored and very stable), and a patent appHcation was filed ia the same year. 

Silicon phthalocyanine-based dyes have also been studied for use in ODS. The synthesis, structural and conformational analysis, and chemical properties of some silicon phthalocyanine-based dyes (Scheme 8) were recently reported.218... 

In contrast to the azo dyes the synthesis of phthalocyanine blue is easy. It is made in one step from readily available compounds phthalic anhydride, urea, and a copper salt. 

Virtually every conceivable chromophore has been used in the synthesis of reactive dyes, including monoazo and disazo species, metal complexes of azo dyes, formazan dyes, anthraquinones, triphenodioxazines, and phthalocyanines. The product lines offered by the major dye producers in most cases feature comparable chromophores, differing primarily in the nature of the reactive systems and the particular substitution patterns adopted. 

In the case of the dye from copper phthalocyanine (C.I. Sulphur Green 25), the synthesis can follow one of two paths ... 

Most reported phthalocyanine derivatives (sulfo-, nitro-, amino-, triphenylmethyl-, polymeric, etc.) are copper complexes, although at present the synthetic chemistry of other d- and /-metal Pc derivatives is being rapidly developed (Examples 30-36) [5,6,116-118]. Some of them (in particular, copper phthalocyanine sulfonic acids) are of industrial interest because of their usefulness as dyes. Phthalocyanine sulfonic acids themselves are prepared both by urea synthesis from sulfonated phthalic anhydride and by the sulfonation of the phthalocyanine [6], Some substituted metal phthalocyanines can be obtained by chemical or electrochemical reduction [118e]. Among a number of reported peculiarities of substituted phthalocyanines, the existence of three electronic isomers for magnesium derivative PcMn was recently confirmed [118f]. 

Tremendous efforts have been paid toward the development of new phthalocyanine molecular materials as well as toward their applications. Recent emphasis in both academic researches and technical field has been put on the design and synthesis of novel phthalocyanine species, the structure-property relationship, self-assembly properties, molecular electronics and opto-electronics, and dye-sensitized solar cells. Although excellent reviews and monographs about phthalocyanines were published several years ago, it is time to provide a survey of a number of new important developments in this fascinating area of phthalocyanine chemistry. The aim of this book is to bring both the academic and industrial researchers an easy way to the new progress of phthalocyanines made lately in related field. 

The insolubilities of phthalocyanines made their analysis difficult and it took some time before a satisfactory structure was elucidated. Initial work was undertaken by the Linstead group at Imperial College in the 1930s that culminated in a series of six back to back papers published in 1934 [14], It was also Linstead who named the compounds in recognition of their synthesis from phthalic anhydride and similarity to the blue cyanine dyes. Definitive characterization of the nickel, platinum and copper phthalocyanine complexes, together with the metal-free compound, was revealed in 1935 following the publication of their X-ray structures by Robertson [15] the copper and metal-free compounds are illustrated in Fig. 7.5. 

The enormous amount of work on phthalocyanins1 reflects their prime importance to the dye and pigment industry and is attested to by the numerous patents in the literature. It is our experience, however, that these materials are rarely pure and that their purification, from unknown impurities, is invariably more troublesome than performing the complete synthesis. Phthalocyanins are stronger o-donors than porphines, and the former stabilize higher oxidation states of coordinated metals,2 while the tetrabenzoporphyrins have properties more characteristic of porphines. 

PCBs and PCDDs. In Diarylide Yellow manufacture, the use of formate buffer to enhance pigment transparency for offset ink was discontinued in the nineteen seventies, when it was realized that polychlorinated biphenyls were being produced as an undesirable by-product of the coupling reaction. In Phthalocyanine Blue crude synthesis, the commonly used solvent, trichlorobenzene, was also discontinued in the US, as a potential source of poly-chlorinated biphenyls. More recently, use of chloranil, manufactured from chlorinated phenols, has been discontinued in the synthesis of dioxazine violet crude and sulfonated dioxazine acid dyes, so as to minimize by-product formation of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/PCDFs). A new grade ofhigh purity chloranil is now produced from hydroquinone for dye and pigment manufacture. 

Porphyrin-like structures received considerable attention because of their interesting chemical and physical behaviors, and because of nature s ubiquitous use of porphyrins in electron-transfer processes. The phthalocyanine (hereafter referred to as Pc) is a porphyrin-like dye that has been known for many years. The word phthalocyanine, from the Creek for naphtha (rock oil) and cyanine (blue), was first used by Linstead in 1933 to describe a new class of organic compounds.Phthalocyanine was probably discovered by accident in 1907. as a by-product during the synthesis of o-cyanobenzamide, but it was not until almost 20 years later that a patent was filed describing a manufacturing process. Linstead and coworkers showed that a vast range of phthalocyanines, the metal (M)-substituted forms of the molecules (hereafter referred to as MPcs), were all based on the structure depicted in Fig. 1. In a classic series of papers, starting in 1935, Robertson and coworkers showed that the enviromnent of the metal atom in MPcs was square planar and coordinated with four pyrrolic N atoms, and moreover, that the entire Pc-molecule was flat within the limits of uncertainty. ... 

Mahmut Dunnus, Hanifi Yaman, Cem Gol, Vefa Ahsen, Tebello Nyokong. (2011). Water-soluble quatemized mercaptopyridine-substituted zinc-phthalocyanines Synthesis, photophysical, photochemical and bovine serum albumin binding properties. Dyes and Pigments 91, 153-163. 

Phthalic anhydride. The feedstocks are either naphthalene or o-xylene, the process being a catalysed air oxidation (see Vol. I, pp. 293, 317, 368). The product is required in large quantities by the plastics industry, the intake in the dye industry being only minor in quantity. It is the feedstock for phthalocyanine production and in the synthesis of anthraquinone intermediates, e.g. quinizarin (for disperse dyes) and 2-methylanthraquinone (for acid dyes). 

Karaoglu HRP, Koca A, Kocak MB (2012) Synthesis, electrochemical and spectroelectrochemical charactmization of novel soluble phthalocyanines bearing chloro and quatmnizable bulky substituents on peripheral positions. Dyes Pigm 92(3) 1005-1017... 

Nombona N, Nyokong T (2009) The synthesis, cyclic voltammetry and spectroelectrochemical studies of Co(II) phthalocyanines tetra-substituted at the alpha and beta positions with phenylthio groups. Dyes Pigm 80(1) 130-135... 

Kilicaslan MB, Kantekin H, Koca A (2014) Synthesis, electrochemicaL in-sim spectroelectrochemical and in-situ electrocolOTimetric characterization of new phthalocyanines containing macrocyclic moieties. Dyes Pigm 103 95-105... 

Karaoglan GK, Gumrukcu G, Koca A, Gul A (2011) The synthesis, characterization, electrochemical and spectroelectrochemical properties of a novel, cationic, water-soluble Zn phthalocyanine with extended conjugation. Dyes Pigm 88(3) 247-256... 

Merck Index Number 218 Chemical/Dye Class Copper phthalocyanine Molecular Formula C56H68CI4CUN16S4 Molecular Weight 1298.93 Physical Form Dark blue-violet powder Solubility Soluble in water, ethanol Melting Point 148 °C Absorption (A ax) 615 nm Synthesis Synthetic methods ... 

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