Naphthalenes 2.6- naphthalenedicarboxylate

Naphthalenedicarboxylic acid has been prepared by fusing dipotassium 2,6-naphthalenedisulfonate with potassium cyanide to give the corresponding dinitrile, which is hydrolyzed by oxidation of 2-methyl-6-acetylnaphthalene with dilute nitric acid at 200 by the thermal disproportionation of potassium a- or /3-naphthoate to dipotassium 2,6-naphthalenedicarboxylate and naphthalene and by the present method. The present method is much more convenient than earlier methods, if a suitable autoclave is available. 

The decarboxylation of mercuric 3- and 4-nitro-l,8-naphthalene-dicarboxylates has been studied to determine substituent electronic effects [Eq. (83)] (95,96), since significant steric effects are unlikely. There is disagreement over the products. In an early study, 3- and 4-nitro-l,8-naphthalenedicarboxylates were found to undergo decarboxylation predominantly in the ring without the nitro group (95), consistent... 

An intriguing intramolecular (3 + 2) photocycloaddition of alkenyl methyl 1,4-naphthalenedicarboxylates has been developed by Kubo et al. [300], Intramolecular (3 + 2) photocycloaddition of alkenyl methyl 1,4-naphthalene di-carboxylates, which contain remote alkene moieties proceeded largely dependent on the chain lengths. On irradiation of benzene or acetonitrile solutions of 406a-c, no reaction was observed despite its chain length. On the other hand, in the photoreactions of 407a-e, intramolecular (3 + 2) photocycloadditions proceeded... 

Alkylene 2,6-Naphthalenedicarboxylate/PTME 2,6-Naphthalene-dicarboxylate Copolymers. Fifty percent alkylene 2,6-naphthalenedicar-boxylate/PTME 2,6-naphthalenedicarboxylate copolymers were prepared using each of the straight-chain, hydroxy-terminated diols from ethylene glycol (2G) to 1,10-decanediol (10G) (Table VIII). In contrast to many of the 50% alkylene terephthalate/PTME terephthalate copolymers of Table II, all of the 2,6-naphthalenedicarboxylate-based copolymers tested exhibit excellent tensile strength and tear strength regardless of the diol used or the melting point of the copolymer. As a consequence of their excellent properties, the 2,6-naphthalenedicarboxylate copolymers have been the subject of several patents (32,33,34). 

Figure 4. The melting points of 50% alkylene 2,6-naphthalene dicarboxylate/FT ME 2,6-naphthalenedicarboxylate copolymers as a function of the melting points of the corresponding poly(alkylene 2,6-naphthalenedicarboxylate) homopolymers...

Regioselective dialkylation of naphthalene is another reaction of considerable interest as 2,6-dialkylnaphthalenes can be oxidised to naphthalene-2,6-dicarboxylic acid, which is used in the synthesis of the commercially valuable polymer, poly(ethylene naphthalenedicarboxylate) (PEN).22 PEN has properties that are generally superior to those of polyethylene terephthalate) (PET) and has become the polymer of choice for a variety of applications such as in films, industrial fibres, packaging, liquid crystalline polymers, coatings, inks and adhesives. However, the high cost of naphthalenedicarboxylic acid has been a major hindrance to widespread application. 

Two potassium atoms transfer an electron each to butadiene forming a dianion transmetallation with o-xylene then gives the potassium-bonded carbanion, which inserts butadiene. A second transmetallation with o-xylene liberates the potassium-stabilized benzylcarbanion, which is the actual catalytic species and generates o-pentenyltoluene. This can then be cyclized to 1,5-dimethyltetralin, which, after dehydrogenation to the corresponding naphthalene and isomerization to the 2,6-isomer, affords 2,6-naphthalenedicarboxylic acid by oxidation. 

C14H1204 dimethyl-2,6-naphthalenedicarboxylate 840-65-3 6.232 32302 C20H28 1-decyi naphthalene 26438-27-7 8.139... 

The same group has investigated the photo-addition of alkenes to 1,2- and 2,3-naphthalenedicarboxylic acid anhydride.No products of addition of the alkene to the naphthalene ring were observed instead the alkene inserts into the C(=0)-0 bond of the anhydride or adds to one of the carbonyl groups to produce an oxetane. By analogy with imides, the insertion reaction can be viewed as an addition to the partial C-o double bond Illustrated by the contributing structure (81) to give adduct (82) which collapses to the isolated insertion product (83). 

Naphthalene-l, 4,5,8-tetracarboxylic acid dianhydride 118, 137, 138, 140, 146, 147 2,6-Naphthalenedicarboxylic acid 196 Nonlinear optical polymers 36... 

Naphthalenedicarboxylic acid 3,4 -Diphenyl ether dicarboxyUc acid 4,4 -Diphenyl ether dicarboxyUc acid 3,4 -Diphenyl sulfide dicarboxyUc acid 4,4 -Diphenyl sulfide dicarboxyUc acid 3,4 -Diphenyl sulfone dicarboxyUc acid 4,4 -Diphenyl sulfone dicarboxyUc acid 3,4 -Benzophenonedicarboxylic acid 4,4 -Benzophenonedicarboxylic acid 1,4-Naphthalene dicarboxyUc acid... 

Graebe (an assistant) and C. Liebermann (a student) in Baeyer s laboratory reduced alizarin to anthraquinone by Baeyer s method of heating with zinc dust, and thus established that alizarin is a derivative of anthracene, and not of naphthalene as had been thought. They proposed a formula for anthracene and synthesised alizarin from anthraquinone. This led to the synthetic alizarin industry, and the decline of natural madder as a dye. The other colour in madder, purpurin, was synthesised by oxidising alizarin by F. de Lalande. Behr and van Dorp obtained anthraquinone by heating o-benzoylbenzoic acid with phosphoric oxide, when ring-closure occurs. They discovered 1 8-naphthalenedicarboxylic acid. ... 

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