2 Naphthylamine- l-sulphonic acid

A kinetic study of the desulphonation of 2-naphthylamine-l-sulphonic acid by hydrochloric, sulphuric and phosphoric acids showed the rate to be proportional to the concentration of hydrogen ions and the aromatic and a mechanism involving the formation of 1-naphthylsulphamic acid was proposed702. 

Chapter IV. a-Chloromethylnaphthalene (IV,23) benzylamine (Gabriel synthesis) (IV,39) iViV-dialkylanilines (from amines and trialkyl orthophosphates) (IV,42) a-naphthaldehyde (Sommelet reaction) (IV,120) a-phenyl-cinnamic acid (Perkin reaction using triethylamine) (IV,124) P-nitrostyrene (IV,129) p-bromonaphthalene and p-naphthoic acid (from 2-naphthylamine-l -sulphonic acid) (IV,62 and IV,164) diphenic acid (from phenanthrene) (IV,165). 

Naphthylamine-5,7-disulphonic acid and 2-naphthylamine-l-sulphonic acid, which are intermediate products in Scheme 4.28, as well as 2-naphthylamine-l,5-disulphonic acid (obtained by careful low-temperature sulphonation of Tobias acid), are all used in the synthesis of azo dyes. 

Naphthylamine-l-sulphonic acid [81-16-3] M 223.3. Crystd under nitrogen from boiling water and dried in a steam oven. 

P-Naphthylacetic acid, 924,925 a-Naphthylacetonitrile, 752, 763 a-Naphthylamine, 561, 568 P-Naphthylamine, 561, 568 carcinogenic properties of, 562 2 Naphthylamine-l-sulphonic acid, 604, 752, 767... 

Naphthylamine is no longer manufactured and its laboratory preparation should never be attempted because of its potent carcinogenic properties. For many preparative purposes (e.g. see 2-bromonaphthalene, cognate preparation in Expt 6.72, and 2-naphthoic acid, Expt 6.154), 2-naphthylamine-l-sulphonic acid may be used. This is obtained commercially by cautious treatment of 2-naphthol with sulphuric acid - the sulphonic acid group entering the 1-position - followed by a Bucherer reaction. 

In the preparation of 2-naphthoic acid (Expt 6.154) the preferred starting material is 2-naphthylamine-l-sulphonic acid (see Section 6.5.4, p. 900). After... 

Diazotise 122g (0.5mol) of 2-naphthylamine-l-sulphonic acid (1) as detailed under 2-bromonaphthalene in Expt 6.72. Prepare copper(i) cyanide from... 

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