Phthalamides

Anthranilic acid. This substance, the ortho amino derivative of benzoic acid, may be conveniently prepared by the action of sodium hypobromite (or sodium hypochlorite) solution upon phthalimide in alkaline solution at 80°. The ring in phthalimide is opened by hydrolysis to phthalamidic acid and the latter undergoes the Hofmann reaction (compare Section 111,116) ... 

Phthalamide. Mix 200 g. of phthalimide (Section IV,169) with 600 ml. of concentrated ammonia solution in a 1 litre beaker and stir mechanically for 24 hours. Filter off the micro-crystalline cake of phthalamide and dry at 100°. The yield is 200 g., m.p. 220° (decomp.). 

Phthalonitrile. In a 1 litre round-bottomed flask, provided with a reflux condenser, place 100 g. of phthalamide and 350 ml. of acetic anhydride. Reflux for 5-6 hours. Add the reaction product whilst still hot cautiously to 700 ml. of boiling water this decomposes the excess of acetic anhydride. Cool in ice, and then render the reaction mixture alkaline with sodium hydroxide solution. Filter ofiF the precipitated crystals at the pump, wash with water, and dry at 100°. The yield of the crude nitrile is 70 g. After one or two recrystallisations from benzene, the m.p. should be 141°—that of pure phthalonitrile. It is usually best to distil the crude nitrile under reduced pressure (Figs. II, 19, 3-4) the distillate has m.p. 137-138°, and the m.p. is raised to 141° after one recrystallisation from benzene. 

AC 94377. The compound l-(3-chlorophthalimide) cyclohexanecarboxamide [51971 -67-6] (Table 3) (45), also known as AC 94377, is a phthalamide that has plant growth regulating properties. It is relatively nontoxic so that its use in floricultural crops appears to be safe. It is mainly used to control stem length and stem numbers in hybrid tea roses (23). However, it has very limited use and is stiH experimental. 

Over the years polymers have been produced suitable for use at progressively higher temperatures. Where this is a requirement, it is usual first to decide whether a rubbery or a rigid material is required. If the former, this has been dealt with by the author elsewhere." If the latter, it is usually convenient to look in turn at polycarbonates, PPO-based materials, polyphenylene sulphides, polysul-phones, polyketones such as PEEK and PEK, polyamide-imides, poly-phthalamides, fluoropolymers, liquid crystal polymers and polyimides. 

Next the product is acylated with bromoacetyl chloride and the glycine equivalent is constructed in place by a Gabriel amine synthesis (phthalamide anion followed by hydrazine) subsequent to which cyclization to benzodiazepine occurs. The synthesis of the tranquilizer quazepam (88) is finished by thioamide conversion with phosphorus pentasulfide. ... 

Phthalic anhydride is also used to make polyester and alkyd resins. It is a precursor for phthalonitrile by an ammoxidation route used to produce phthalamide and phathilimide. The reaction scheme for producing phthalonitrile, phthalamide, and phathilimide is shown in Figure 10-17. ... 

Phenyl-1 -propanone 1 - Pheny 1-2-propanone Phenyl salicylate Phenyl vinyl ether Phthalamide 1.3- Phthalic acid 1.4- Phthalic acid Phthalic anhydride Phthalonitrile Piperidine 14.85... 

Arsenic uptake in rabbit intestine is inhibited by phosphate, casein, and various metal-chelating agents (USEPA 1980). Mice and rabbits are significantly protected against sodium arsenite intoxication by (V-(2,3-dimercaptopropyl)phthalamidic acid (Stine et al. 1984). Conversely, the toxic effects of arsenite are potentiated by excess dithiols, cadmium, and lead, as evidenced by reduced food efficiency and disrupted blood chemistry in rodents (Pershagen and Vahter 1979). 

An example of the second effect is provided by mono-sec-butyl phthalamide (17a) (56). In the crystal the two enantiomers of this molecule are miscible in all proportions. The racemate crystallizes in space group PI (two general positions in the unit cell) with four molecules per unit cell. Thus there are two molecules in the asymmetric unit. The sec-butyl moieties adopt the anti conformation (the two geometries are shown schematically in 17b) and exhibit conformational disorder to different extents at the two symmetry-independent sites. 

These facts can be explained by a simple comparison of the stretched conformations of poly(p-phenylene terephthalamide) and poly(m-phenylene iso-phthalamide). Whereas the all-para linked polyamide can build up many hydrogen bonds to the neighboring molecules, this is less possible for the all-wcta linked polymer ... 

The presence of a phenylene group in these polyamides and polyesters increases the heat resistance dramatically. Thus the Tg of polyethylene tere-phthalamide (aramid) is 300 °C and that of PET is 265 C. Poly-/>-oxybenzoate (Ekonol) does not melt but decomposes at 480 C. 

Model compound studies indicated that both the nature of the base, the nature of the alkyl ester and the amide group exerted pronounced effects on the observed imidization rates [59]. As illustrated in Table 6, the imidization rate of monomethyl p-methoxyphenyl phthalamide tracks the general basicity of the... 

Table 6. Effect of base strength on the imidization rate of monomethyl ester p-methoxyphenyl phthalamide at 23.3 °C.

Table 7. Imidization rates of various monoalkyl ester aryl phthalamides in W-methyl pyrollidone...

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