Phthalimides phthalic acid anhydride

In a typical run, the nitrile 1 (30 mmol) and phthalic acid 2 (36 mmol) were introduced into the reactor, and heated under stirring. In the kinetic studies, time zero is taken at complete dissolution of the phthalic acid. At the desired reaction time, the reactor was rapidly cooled in a water-ice mixture and then chloroform (30 mL) was added. The mixture was stirred for 5 min and then the solid was filtered off. The chloroform solution contains the unchanged nitrile 1, the amide and the carboxylic acid 3. The residual solid contains unchanged phthalic acid 2, phthalimide 4, and as the major component, phthalic anhydride 5. The volume of the chloroform solution was adjusted to 50 mL and naphthalene was added as an internal standard. The resulting solution was analyzed by GLC. 

Equations (II) to (IX) illustrate basic methods of preparation, but many variations are used, particularly in industry, to obtain an economic yield. Phthalic acid, phthalamide, phthalimide, and phthalic anhydride, together with urea, are often used instead of phthalonitrile, and catalysts such as ammonium molybdate or zirconium tetrachloride may be employed (249, 251, 269). The reaction between phthalonitrile and metals (finely divided or acid-etched) is usually very vigorous at 250°-300°C, sufficient heat being generated to maintain the reaction temperature. This is an illustration of the ease with which the phthalocyanine skeleton is formed. Even more surprising are the observations that palladium black (118) and gold (189) will dissolve in molten phthalonitrile. Reaction (III) between phthalonitrile and a finely divided metal, metal hydride, oxide, or chloride is perhaps the most generally employed. For the unstable phthalocyanine complexes such as that of silver (11), the double decomposition reaction... 

Phosphine(s), chirality of, 314 Phosphite, DNA synthesis and, 1115 oxidation of, 1116 Phospholipid, 1066-1067 classification of, 1066 Phosphopantetheine, coenzyme A from. 817 structure of, 1127 Phosphoramidite, DNA synthesis and, 1115 Phosphoranc, 720 Phosphoric acid, pKa of, 51 Phosphoric acid anhydride, 1127 Phosphorus, hybridization of, 20 Phosphorus oxychloride, alcohol dehydration with. 620-622 Phosphorus tribromide, reaction with alcohols. 344. 618 Photochemical reaction, 1181 Photolithography, 505-506 resists for, 505-506 Photon, 419 energy- of. 420 Photosynthesis, 973-974 Phthalic acid, structure of, 753 Phthalimide, Gabriel amine synthesis and, 929... 

Phthalocyanines have been synthesized with nearly all metals of the periodic table.77 Normally they are formed in a single-step reaction from available derivatives of phthalic acid, in particular phthalic acid (see Section 2.1.1.1.), phthalic anhydride (see Section 2.1.1.2.), phthalimide (see Section 2.1.1.3.), 2-cyanobenzamide (see Section 2.1.1.4.), phthalonitrile (see Section 2.1.1.5.), isoindolinediimine (see Section 2.1.1.6.), or 1,2-dibromobenzene (see Section 2.1.1.7.), usually in a high-boiling solvent or by heating the neat components.1 4... 

Phthalic acid, 32, 67 Phthalic anhydride, 32, 19 PHTHALIMIDE, N-2-BROMOETHYL-, 32, 18 PlMELIC ACID, 7-0X0-, DIETHYL ESTER,... 

The baking process has remained much the same until the present day at a stoichiometric ratio of 1 4, phthalic anhydride or phthalic acid reacts with an ammonia releasing compound. The reaction may also start from other suitable materials, such as phthalic acid derivatives, including phthalic acid esters, phthalic acid diamide, or phthalimide. Appropriate ammonia releasing agents include urea and its derivatives, such as biuret, guanidine, and dicyanodiamide. The fact that a certain amount of urea decomposes to form side products makes it necessary to use excess urea. Approximately 0.2 to 0.5, preferably 0.25 equivalents of copper salt should be added for each mole of phthalic anhydride. 0.1 to 0.4 moles of molybdenum salt per mole of phthalic anhydride is sufficient. The reaction temperature is between 200 and 300°C. 

Carboxy carbons of methyl benzoates are shielded by electron-withdrawing substituents in the oposition of the benzene ring [320] (Table 4.38). Carbonyl shifts of phthalic acid diesters and phthalimide are larger than those of phthalic anhydride [321]. fi effects of the O-alkyl group in the esters and hydrogen bonding of the imide are the obvious reasons. 

Carboxylic acids react with aryl isocyanates, at elevated temperatures to yield anhydrides. The anhydrides subsequently evolve carbon dioxide to yield amines at elevated temperatures (70—72). The aromatic amines are further converted into amides by reaction with excess anhydride. Ortho diacids, such as phthalic acid [88-99-3], react with aryl isocyanates to yield the corresponding N-aryl phthalimides (73). Reactions with carboxylic acids are irreversible and commercially used to prepare polyamides and polyimides, two classes of high performance polymers for high temperature applications where chemical resistance is important. Base catalysis is recommended to reduce the formation of substituted urea by-products (74). 

The benzenedisulfonic acids are of little interest, except that benzene-1,3-disulfonic acid is a source of 1,3-dihydroxybenzene (see Chapter 4). The benzene dicarboxylic acids are more important. Benzene-1,2-dicarboxylic acid (phthalic acid, 8) can be converted into phthalic anhydride (9), which is a typical acid anhydride, reacting with amines and alcohols and also taking part in Friedel-Crafts reactions. Phthalimide (10), produced by reaction of the anhydride with ammonia, is weakly acidic and forms a potassium salt with ethanolic potassium hydroxide. 

This shows that phthalimide is a compound of an anhydride type formed by loss of ammonia from phthalamide just as phthalic anhydride is formed from phthalic acid by the loss of water. Like other acid amides and imides phthalimide forms salts by replacement of the... 

The details of this synthesis will be explained under naphthalene (p. 766). The synthesis of anthranilic acid from ortho-i hthalic acid takes place according to the following reactions. Phthalic acid, or better phthalic anhydride, by treatment with ammonia yields phthal-amidic acid, which in turn yields phthalimide. 

Hofmann Reaction.—In the reaction with phthalic acid or anhydride and ammonia the phthalamidic acid may be isolated without going on to phthalimide. In this case the action of potassium hydroxide is simply neutralization and formation of the above salt. The Hofmann reaction with phthalamidic acid may be represented in steps as follows ... 

Naphthalene to Anthranilic Acid.—Such a cheap source was found in naphthalene which was converted into anthranilic acid, orthoamino benzoic acid, and this by treatment with chlor acetic acid yields phenyl glycine ortho-carboxylic acid. The complete synthesis is as follows Naphthalene is oxidized to or// o-phthalic acid which then yields phthalic anhydride. This with ammonia, as ammonium carbonate, yields phthalimide or phthalamidic acid. 

Like other anhydrides, cyclic anhydrides react wfth ammonia to yield amides in this case the product contains both --CONH2 and —COOH groups. If this acid-amide is heated, a molecule of water is lost, a ring forms, and a product is obtained in which two acyl groups have become attached to nitrogen compounds of this sort are called imides. Phthalic anhydride gives phthalamic acid and phthalimide ... 

The most common synthetic method for the synthesis of metal-containing Pcs involves the cyclotetramerization of phthalic acid, phthalic anhydride, 2-cyanobenzamide, phthalimide, diimino-isoindoline, or phthalonitrile at elevated temperatures (>200 °C) in the presence of a metal or metal salt. These reactions can be carried out either in a suitable solvent or in the melt. It should be noted that the use of a metal halide in the melt often leads to a monohalogenated Pc. Except for phthalonitrile and diiminoisoindoline cyclotetramerizations, a nitrogen source is required,... 

Rearrangement of phthalic acid derivatives. Treatment of phthalic anhydride with ammonia and NaOH leads to phthalamic acid (8), which rearranges with NaOCl to IA.33,34 The same result can be achieved starting with phthalimide (7)8,23,35-38 or N-chlorophthalimide (9).39 Similar reactions starting with phthalic acid or anhydride via the azide (5) also give IA6,40,41 (see Scheme l). 

---