6654-67-7

Upstream product

• 91-20-3 naphthalene 
• 1655-29-4 disodium 1,5-naphthalenedisulfonate 
• 7664-93-9 sulfuric acid 
• 581-75-9 naphthalene-2,6-disulfonic acid 

Relevant academic research and scientific papers

The positional reactivity order in the sulfur trioxide sulfonation of benzene and naphtalene derivatives containing an electron-withdrawing substituent

The reaction of sulfur trioxide with derivatives of benzene and naphthalene containing an electron-withdrawing substituent, viz.-SO3H, -SO2Ph, -NO2, -CHO, -COPh, -CO2H, and -CO2Me, in dichloromethane as solvent at ca. 22 deg C has been studied by analysis of the resulting mixtures of the sulfo derivatives with 1H-NMR.The initial sulfonation of the benzene derivatives yields the corresponding 3-sulfonic acid (3-S) and subsequently, with the exception of nitrobenzene and methyl benzoate, small amounts of 3,5-S2.Benzenesulfonic acid in addition undergoes sulfonylation giving 3,3'-di- and 3,5,3'-trisulfodiphenyl sulfone.Monosulfonation of naphtalene-1-S yields the 1,5-S2, 1,6-S2 and 1,7-S2 derivatives in a ratio of 71:20:9.On using a large excess of SO3, the eventual products are 1,3,5-S3, 1,3,6-S3 and 1,3,5,7-S4.Monosulfonation of naphthalene yields 5-S, 6-S, 7-S and 8-S in a 55:9:6:30 ratio, that of 1-benzoylnaphthalene 5-S, 6-S and 7-S in a ratio of 83:11:6, and 1-nitronaphtalene only the 5-S.The absence of peri sulfonation with 1-sulfo-, 1-benzoyl- and 1-nitronaphthalene is due to prohibitive steric hidrance. 1-Naphthoic acid and its methyl ester upon SO3 sulfonation and aqueous work-up both yield 5- and 8-sulfonaphthoic acid in a ratio of 65:35 and 77:21, respectively.The initially formed peri-substituted product is the intramolecular anhydride of 8-sulfo-1-naphthoic acid (5).All the 2-substituted naphthalenes yield 5-S and 8-S upon SO3 sulfonation of which the former sulfo isomer is far in excess.The positional reactivity orders for the SO3 sulfonation of the monosubstituted naphthalene derivatives are discussed in terms of the difference in reactivity of the α- and β-positions, and the steric and electronic effects of the deactivating substituent.

Naphthalenetetrayltetrakis(sulfonylimino)-tetrabenzene di- and tricarboxylic acids

Naphthalenetetrayltetrakis(sulfonylimino)tetrabenzene di- and tricarboxylic acids and salts thereof useful as complement inhibitors and the process of making such compounds.

Process for the preparation of naphthalene-1,3,5-trisulphonic acid

A process is provided for the preparation of naphthalene-1,3-5,-trisulphonic acid from 1,5-disulphonated naphthalene, which comprises sulphonating 1,5-disulphonated naphthalene, in the form of a mixture which has been obtained by mixing naphthalene and SO3 in the presence of an inert solvent at temperatures in the range of -40° to +20° C., the ratio of SO3 added to naphthalene added having been in the range of 2.5 to 10 mols of SO3 per mol of naphthalene during the entire addition, at 60° to 110° C. in anhydrous sulphuric acid with oleum, with prior or concurrent separation of the inert solvent. The resulting product is a known intermediate for the formation of azo dyestuffs.

Naphthalenetetrayletrakis(sulfonylimino)-aryl disulfonic acids and salts thereof

Naphthalenetetrayltetrakis(sulfonylimino)-aryl disulfonic acids and salts thereof useful as complement inhibitors.

Naphthalenetetrayltetrakis(sulfonylimino)-aryl multicarboxylic acids and salts thereof

Naphthalenetetrayltetrakis(sulfonylimino)-aryl multicarboxylic acids and salts thereof useful as complement inhibitors.