EP 0000493 B1 19800109 - PROCESS FOR THE PREPARATION OF 1-AMINO-8-HYDROXY-NAPHTHALENE-3,6-DISULPHONIC ACID (H ACID).
Title (en)
PROCESS FOR THE PREPARATION OF 1-AMINO-8-HYDROXY-NAPHTHALENE-3,6-DISULPHONIC ACID (H ACID).
Publication
Application
Priority
DE 2732291 A 19770716
Abstract (en)
[origin: US4178308A] A process has been invented for the preparation of a mono-alkali metal salt of 1-amino-8-naphthol-3,6-disulphonic acid comprising reacting 1-naphthylamine-3,6,8-trisulphonic acid and/or a salt thereof and/or a naphthylamine-trisulphonic acid isomer mixture and/or salt thereof with an alkali metal hydroxide solution at elevated pressure and elevated temperature and in the presence of an alcohol or alcoholate, and separating out the mono-alkali metal salt by acidification. The process results in the procurement of higher yields of the desired product and in the formation of less by-products.
IPC 1-7
IPC 8 full level
C07C 309/50 (2006.01); C07C 67/00 (2006.01); C07C 301/00 (2006.01); C07C 303/22 (2006.01); C07C 303/32 (2006.01); C22B 34/12 (2006.01); H03D 13/00 (2006.01)
CPC (source: EP US)
C22B 34/12 (2013.01 - EP US)
Designated contracting state (EPC)
BE CH DE FR GB
DOCDB simple family (publication)
EP 0000493 A1 19790207; EP 0000493 B1 19800109; BR 7804546 A 19790320; DE 2732291 A1 19790201; DE 2857516 D1 19800214; IT 1105430 B 19851104; IT 7850300 A0 19780714; JP S5419954 A 19790215; JP S6136509 B2 19860819; US 4178308 A 19791211
DOCDB simple family (application)
EP 78100354 A 19780711; BR 7804546 A 19780714; DE 2732291 A 19770716; DE 2857516 T 19780711; IT 5030078 A 19780714; JP 8525578 A 19780714; US 92003378 A 19780628