Azoverbindungen,deren Herstellung und Verwendung

摘要

1346367 Amino naphthalene sulphonic acids CIBA-GEIGY AG 27 Oct 1971 [27 Oct 1970 4 Oct 1971] 49917/71 Heading C2C [Also in Division C4] Compounds of formula where R 1 is H or C 1 -C 4 alkyl are prepared by sulphonation of the corresponding 2-amino-1- naphthylalkanesulphonic acids in oleum at normal or elevated temperatures. In Example 1, 2 - amino - 1 - sulphomethylnaphthalene is reacted with sulphuric acid monohydrate in oleum at 20-25‹ C. 2-amino-1-α-sulphoethylnaphthalene - 5 - sulphonic acid is prepared analogously. The compounds are used as intermediates in the preparation of azo dyestuffs.