Chlorophthalic anhydride

Only a minor amount of chlorinated copper phthalocyanine, for instance, especially in the 4-position of the copper phthalocyanine molecule, prevents a change of modification from a to (3. Approximately 3 to 4% chlorine is commonly used, which corresponds to the formula CuPc-Cl0.5, also referred to as semi-chloro-CuPc . The phthalic anhydride/urea synthesis, for instance, affords a partially chlorinated product if 4-chlorophthalic anhydride is added to the reaction mixture. Copper chlorides in the phthalonitrile process have the same effect. 

The most magnificent dyes, which are chiefly used in the dyeing of silk, are relatives of eosin obtained from di- and tetra-chlorophthalic anhydride (phloxine, rose bengale). The (basic) rhodamines also belong to this class. They are produced by condensation of phthalic anhydride with m-aminophenols (in place of resorcinol) the dye containing the diethylated NH2-group, in particular, is of great technical importance. 

The protected amino acid tetrachlorophthalimidoacetic acid synthesised from tetra-chlorophthalic anhydride and glycine using DMF as the solvent was conducted on a molar scale to yield 300 g of the product after 8 min (Scheme 9.8)113. 

Venables KM, Newman Taylor AJ Exposure-responsive relationships in asthma caused by tetra-chlorophthalic anhydride. J Allergy Clin Imunol 1990 85 55-58. (NC)... 

Oxydiphthalic anhydride (4,4 -ODPA) can be prepared from chlorophthalic anhydride in < -dichlorobenzene and potassium carbonate. Hexaethylguanidinium chloride is used as a phase transfer catalyst. ... 

Chloro-p-phenylenediamine, 431 Chlorophenylsulfonyl phenoxide, 245 Chlorophthalic anhydride, 476 Chlorophyll, 49... 

The association constant and heat of hydrogen-bonding between dimethyl sulphoxide and (inter alia) pentafluorobenzene in carbon tetrachloride have been measured, and the same solvent apparently contributes to the strength of the complexes formed between the methylbenzenes and fiuoranll, chloranil, or tetra-chlorophthalic anhydride. ... 

Yellow colour appears immediately after mixing of the two reagents which fades out progressively as the reaction proceeds. This colour is due to the absorption of a n—n type CT complex amine-anhydride of composition 1 1. The reactions have been carried out in a series of moisture-free aprotic solvents possessing general and specific effects. A typical exemple is given by the quaternization of trie thy lamine with tetra-chlorophthalic anhydride (Table II). 

During the course of these reactions, we also found that the imide moiety was activating enough to allow chloro-substituted phthalimides to react in a manner similar to the diiodo compounds above. Enhanced rates were seen when iodide ion was present in the reaction mixture (14). Thus, a variety of PIAs derived from 4-chlorophthalic anhydride were made, (Table HI). 

Pigment Blue 15 [147-14-8] 74160 copper phthalocyanine condensation of phthalic anhydride with urea, in presence of copper ions, with or without added chlorophthalic anhy-dride subsequent conversion to alpha-phase and stabilization, if necessary... 

Lowering the reaction temperature or adding urea or basic solvents decreases the extent of chlorination. Solvents such as nitrobenzene, trichlorobenzene, alcohols, glycols, pyridine, and aliphatic hydrocarbons are employed. By using substituted phthalic acids such as 4-chlorophthalic acid anhydride, 4-sulfophthalic acid anhydride, or 4-nitrophthalimide, phthalocyanines with inner substitution can be produced. The products can often be purified by sublimation in vacuo at 300-400 °C. Soluble Pc s can be purified by recrystallization. 

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