Schaffer acid

Naphthalenediol. This diol is prepared by the alkah fusion of 2-hydroxynaphthalene-6-sulfonic acid (Schaffer acid) at 290—295°C. Schaffer acid is usually produced by sulfonation of 2-naphthol with the addition of sodium sulfate at 85—105°C. This acid is also used as a coupling component in the production of a2o dyes such as Acid Black 26. 2,6-Naphthalenediol is used as a component in the manufacture of aromatic polyesters which, as is also tme of the corresponding amides, display Hquid crystal characteristics (52). 

Side Note 5.2. Large-Scale Preparation of a Schaffer Acid... 

The site at which the sulfo group appears in / -naphthol depends very markedly on the temperature. At low temperatures 2-hydroxy-1-naphthalene-sulfonic acid is obtained 150 at higher temperatures or when an excess of sulfuric acid is used, migration of the sulfo group leads to 7-hydroxy- 1-naph-thalenesulfonic acid (croceic acid), and finally at 110° almost exclusively to 7-hydroxy-2-naphthalenesulfonic acid (Schaffer acid). Further treatment with an excess of sulfuric acid leads to / -naphthol-di- and -tri-sulfonic acids, which are important for the dyestuffs industry but which will not be discussed in detail... 

Another important derivative of 2-naphthol is Schaffer acid, which is produced by sulfonation of 2-naphthol with the addition of sodium sulfate at 85 to 105 °C. 

Schaffer acid is used as a coupling component in the production of azo dyes such as Acid Black 26. 

Naphthol-6-sulfonic acid. Schaffer acid. p-Naphtholsulfonic... 

Schaffer s acid, CioHg04S. 2-hydroxy-7-naphthalene sulphonic acid. Obtained by sulphonating 2-naphthol with a small amount of sulphuric acid at a higher temperature than is used for the preparation of crocein acid. A valuable dyestuff intermediate. 

Altschul S F, T L Madden, A A Schaffer, J Zhang, Z Zhang, W Miller and D J Lipman 1997. Gapped BLAST and PSI-BLAST A New Generation of Protein Database Search Programs. Nucleic Acids Research 25 3389-3402. 

Altschul SF, Madden TL, Schaffer AA, Zhang J, Zhang Z, Miller W, Lipman DJ, Gapped BLAST and PSI-BLAST a new generation of protein database search programs. Nucleic Acids Res 1997 25 3389-402. 

Schaffer, J. E. and H. F. Lodish. Expression cloning and characterization of a novel adipocyte long chain fatty acid transport protein. Cell 1994, 79, 427-436. 

Another heteroatom in the feed which affects performance and product quality is nitrogen. Basic nitrogen in the feed tends to lower cracking activity by adsorbing onto the acid sites of the surface of the cracking catalyst. The work of Wu and Schaffer (5), showed that not all nitrogen compounds were equally harmful. They... 

Completely different results from those obtained in the photooxidation of 2.4.6-tri-tert-butyl-X phosphorin 24 (p. 54) are obtained in the photooxidation of 1.1-dimethoxy-2.4.6-tri-tert-butyl-X -phosphorin 183, as Schaffer has found. In this case the 2-hydroxy-endoxy-phosphinic acid methyl ester 213 can be isolated in about 20% yield. Its formation can be explained by assuming normal 1.4-addition to 212 as the primary product which is transformed to 213 by hydrolytic ring cleavage of the peroxide bridge, followed by loss of methanol. 

R. Schaffer and H. S. Isbell, Aldonic acids, Methods Carbohydr. Chem., 2 (1963) 11-12. 

Naphthols and Naphtholsulfonic Acids as Coupling Components. This series includes two important acid dyes with very similar structures C.I. Acid Red 88 (see Section 3.9.3), derived from diazotized naphthionic acid and 2-naphthol, and C.I. Acid Red 13, 16045 [2302-96-7] (2), from naphthionic acid and Schaffer s acid. Both are all-purpose dyes which, because of their attractive red shades, are still in use today in many areas of textile dyeing and also for leather and paper dyes. Wool dyeings produced with these dyes exhibit moderate fastness levels. 

Collingridge, G. L., Kehl, S. J. and McLennan, H. (1983) Excitatory amino acids in synaptic transmission in the Schaffer collateral-commissural pathway of the rat hippocampus. J Physiol (Lond) 334, 33-46. 

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