Naphthalene, condensation

Consecutive condensations of 2-naphthol, allylamine, and dibromomethane comprised another route to naphthalene-condensed 1,3-oxazines. A preheated mixture of allylamine and dibromomethane was reacted with 2-naphthol 152 to yield the aminophenol intermediate 520, which was cyclized with the salt formed in the reaction of dibromomethane and diethylamine to give 3-allyl-3,4-dihydro-2//-naphth[l,2-< ][l,3]oxazine 521 on further reaction (Scheme 98) <2004SC2253>. 

Modified Naphthalene condensate Cotton, Rayon, Nylon... 

Chem. Descrip. Sulfonated naphthalene condensate, sodium salt (75-80%) and sodium sulfates (20-25%)... 

Chem. Descrip. Sulfated naphthalene condensation prod, of high m.w. Uses Dispersant, wetting agent, grinding aid for pigments, fillers, carbon bik. in aq. systems plasticizer in concrete, facilitates the reduction of the water amt. 

For a pitch from the pyrolysis of naphthalene, heptameric and octameric naphthalene condensation products have been postulated as model mesogens the corresponding molecular weights are 878/876 and 1006/1008 (Figure 13.4). 

BLANCOL naphthalene condensates are excellent dispersants suitable for such applications as leather treatment, heavy metal cleaners and pigment dispersion. 

Chem. Descrip. high m.w., sulfonated naphthalene condensate Chem. Analysis Water < 7%... 

Chem. Descrip. Sulfated naphthalene condensation prod, of high m.w. ionic Nature Anionic... 

Use a 500 ml. three-necked flask equipped as in Section IV,19, but mounted on a water bath. Place 128 g. of naphthalene and 45 ml. of dry carbon tetrachloride in the flask, and 177 g. (55 ml.) of bromine in the separatory funnel. Heat the mixture to gentle boiling and run in the bromine at such a rate that little, if any, of it is carried over with the hydrogen bromide into the trap this requires about 3 hours. Warm gently, with stirring, for a further 2 hours or until the evolution of hydrogen bromide ceases. Replace the reflux condenser by a condenser set for downward distillation, stir, and distil off the carbon tetrachloride as completely as possible. Mix the residue with 8 g. of sodium... 

Purification of solid by recrystallisation acetanilide from water naphthalene from methylated spirit (III,5). Use 1 g. of solid, 25 ml. flask and short water condenser. 

The accepted configuration of naphthalene, ie, two fused benzene rings sharing two common carbon atoms in the ortho position, was estabUshed in 1869 and was based on its oxidation product, phthaUc acid (1). Based on its fused-ring configuration, naphthalene is the first member in a class of aromatic compounds with condensed nuclei. Naphthalene is a resonance hybrid ... 

Naphthalenesulfonic Acid—Formaldehyde Condensates. The sodium salts of the condensation products of naphthalenesulfonic acid with formaldehyde constitute an important class of compounds which are mainly used in the area of concrete additives (32,33), agricultural formulations, mbber formulations, and synthetic tanning agents. They are also used in photographic materials (34). Hampshire Chemical Co. and Henkel of America, Inc., are the largest suppHers of naphthalene sulfonate in concrete additives (superplasticizer) and reportedly hold 75—80% of this market. It was estimated that naphthalene sulfonate demand from U.S. producers would reach approximately... 

In 1994 estimated naphthalene consumption in western Europe and Japan for the production of alkylnaphthalene sulfonates, naphthalene sulfonate formaldehyde condensates, and synthetic tanning agents was... 

The dianhydride of 1,4,5,8-naphthalene tetracarboxyhc acid [81-30-1] has been of research interest for the preparation of high temperature polymers, ie, polyimides. The condensation of the dianhydride with o-phenylenediamines gives vat dyes and pigments of the benzimidazole type. 

Pigment Orange 43 [4424-06-0] 71105 Perinone condensation of naphthalene-1,4,5,8-tetracarboxyhc acid dianhydride with o-phenylenediamine, and separation of trans isomer... 

The main chain of these polymers contains, as the principal component, five- or six-membered heteroaromatic rings, ie, imides, which are usually present as condensed aromatic systems, such as with benzene (phthalimides, 3) and naphthalene (naphthalimides, 4) rings. 

Includes naphthalene sulfonates and naphthalene sulfonate formaldehyde condensates. 

There are three main uses for naphthalene sulfonic acid derivatives (75—79) as naphthalenic tanning material alkyl naphthalene sulfonates for industrial appHcations as nondetergent wetting agents and as dye intermediates. Consumption of naphthalene sulfonates as surfactants accounts for a large portion of usage. Naphthalene sulfonate—formaldehyde condensates are also used as concrete additives to enhance flow properties. Demand for naphthalene sulfonates in surfactants and dispersent appHcations, particularly in concrete, was expected to increase into the twenty-first century. Consumption as of 1995 was 16 x 10 kg/yr. 

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