Terephthalonitrile oxide

The latter procedure was used in syntheses of stable nitrile oxides such as P,P-diphenylacrylonitrile oxide and 2,6-diphenylbenzonitrile oxide (22), a series of functionally substituted 2,6-dimethylbenzonitrile oxides (29), as well as 2,4,6-triethylbenzene-l,3-dicarbonitrile oxide (29), stable bis(nitrile oxides) of a novel structure 6, in which two benzene rings, bearing hindered fulmido groups are connected with a bridge (30), tetrachloroisophthalo- and terephthalonitrile oxides (31). Stable o-sullamoylbenzonitrile oxides with only one shielding substituent were also prepared using NaOCl/NaOH in a two-phase system (20, 32). 

It is evident that reactions of unsaturated polymers with bisnitrile oxides lead to cross-linking. Such a procedure has been patented for curing poly(butadiene), butadiene-styrene copolymer, as well as some unsaturated polyethers and polyesters (512-514). Bisnitrile oxides are usually generated in the presence of unsaturated polymers by dehydrochlorination of hydroximoyl chlorides. Cross-linking of ethylene-propylene-diene co-polymers with stable bisnitrile oxides has been studied (515, 516). The rate of the process has been shown to reduce in record with the sequence 2-chloroterephthalonitrile oxide > terephthalonitrile oxide > 2,5-dimethylterephthalonitrile oxide > 2,3,5,6-tetramethylterephthalo-nitrile oxide > anthracene-9,10-dicarbonitrile oxide (515). 

Some orientation was retained on thermal polymerization of p-benz-amidostyrene when polymerization was carried out below the polymer glass transition temp>erature 66). Again the monomer crystal has a layer structure separating reactive radicals. The reaction proceeded in successive layers of the monomer crystal form the outside to the inside without induction period. However, the retained orientation detected by optical microscopy and infrared dichroism disappeared above the glass transition temperature of the polymer. Again no path to a polymer crystal structure seems to be available in this reaction. The polymer produced is slightly less dense than the monomer crystal since it is amorphous (6K5). Similar orientation in the amorphous state was found on polymerization of terephthalonitril oxide aystals 67). 

Another possible reaction of this type may lie behind US Patent 3 390 204 which claims that terephthalonitrile oxide will cross-link rubber in solution. The reaction in this case is presumably ... 

I.4.2.I. Synthesis and Modification of Polymers Unstable bis(nitrile oxide), generated by dichloroglyoxime dehydrochlorination, polymerizes in solution to give poly(furoxan) or (in the presence of 1,3-dienes) gives rise to their being cross-linked (500). Polymerization of terephthalonitrile dioxide and its... 

Unsaturations of hydroxy-containing compounds are reduced on reaction with nitrile oxides such as tetramethyl terephthalonitrile N,N -dioxide (506) or 1,3,5-triethylbenzene-2,6-dicarbonitrile oxide (507). The reaction of a nitrile oxide with terminal unsaturation, associated with the preparation of a poly-ol from propylene oxide, reduces the mono-ol content of the poly-ol composition. Thus, stirring a solution of an ethylene oxide-propylene oxide copolymer with an OH content of 2.39% and vinyl unsaturation of 3.58% in THF with l,3,5-triethylbenzene-2,6-dicarbonitrile oxide for 1 min results in an effective removal of the terminal unsaturation. 

Phthalic acid (1,2-benzene dicarboxylic acid), isophthalic acid (1,3-benzene dicarboxylic acid), and terephthalic acid (1,4-benzene dicarboxylic acid) are made by the selective oxidation of the corresponding xylenes. Terephthalic acid may also be produced from the oxidation of naphthalene and by the hydrolysis of terephthalonitrile. 

C.. .. terephthalonitrile radical anion (Eq. 21.7), a species that is oxidized reversibly (Eq. 21.8) at this potential when the potential scan is resumed in the positive-going direction. Note that the reduction of terephthalonitrile to its radical anion is not seen until the second negative-going potential sweep is made. 

Aromatic nitriles hydrogenate to primary amine over palladium-on-carbon in ethanol-HCl or acetic acid" finely divided Ni (Raney Ni) in ethanol/NH3 [equation (f)]. Rhodium hydroxide and (7 3) rhodium-platinum oxide inhibited by LiOH convert ben-zonitrile to benzylamine, and isophthalonitrile or terephthalonitrile to the corresponding diamines [equation (g)]. ... 

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