Peri acid

In some cases where it is difficult to carry out the Bucherer reaction successfully, it is easier to prepare N-arylnaphthylamines by heating together a naphthylamine and an arylamine. In particular, this reaction is useful in the preparation (Scheme 4.24) of 1-phenylaminonaphthalene-8-sulphonic acid (4.34 N-Phenyl Peri acid) and its N-4-methylphenyl analogue (Tolyl Peri acid), both of which intermediates are valuable components for the production of navy blue dyes. 

Nitration of naphthalene-1-sulphonic acid produces two isomeric nitronaphthalenes that have very similar solubilities. It is convenient to reduce the mixture without separation, giving a mixture of l-naphthylamine-8-sulphonic acid (4-44 Peri acid) and 1-naphthylamine-5-sulphonic acid (4.45 Laurent s acid), as in Scheme 4-29. These two... 

Fig. 3.107. Comparison of micro-HPLC separations of aromatic sulphonic acids in different mobile phases (a) 0.005 M tetrabutylammonium hydrogensulphate (TBAS) in 15 per cent (v/v) methanol in water (1) Laurent acid, (2) amino-F-acid, (3) Cleve-1,6- and Peri acids, (4) unidentified impurity, (5) Cleve-1,7-acid and (6) unidentified impurity, (b) 0.005 M tetrabutylammonium hydrogensulphate (TBAS) in 15 per cent (v/v) methanol in water with 0.01 M /Lcyclodextrin (CD) (1) Laurent acid, (2) amino-F-acid, (3) Cleve-1,6-acid, (4) Peri acids, (5) unidentified impurity, (6) Cleve-1,7-acid and (7) unidentified impurity. Column, Biosphere Si C18, 162 X 0.32 mm i.d. flow rate 5 pl/min, column temperature ambient, detection, UV, 220-230 nm. Reprinted with permission from P. Jandera et al. [164].

Coupling H acid to l-(phenylamino)naphthalene-8-sulfonic acid (A-phenyl peri acid) yields C.I. Acid Blue 92 (see Section 3.9.3). On wool it produces a very pure blue of good lightfastness and with moderate wetfastness and adequate leveling power. 

The most important dyes of the type D->M->K are black and navy blue wool dyes, which contain as the middle component M chiefly 1-naphthylamine or 1-naphthylamine-7-sulfonic acid and as the coupling component K A-phenyl peri acid (A-phe ny 1 a m i n o n a p h th a 1 c n c - 8 - s u 1 fo n i c acid), A-tolyl peri acid, and naphthol or 1-naphthylamine derivatives. Examples of these high-yield and very wash- and lightfast dyes are C.I. Acid Black 24, 26370 (see Section 3.9.3), which is manufactured by coupling diazotized 1-naphthylamine-5-sulfonic acid to 1-naphthylamine, further diazotization of the aminomonoazo dye, and coupling to iV-phenylperi acid and C.I. Acid Blue 113, 26360 [3351-05-1] (20). This blue dye is very important in the dyeing of wool and polyamide. 

It is known as naphthalidinesulplionic acid or simply as Laurent s acid. It is usedj but not to any great extentj in the manufacture of azo-colours. The more easily soluble sodium salt obtained above yields a-naphthylaminesulphonic acid S (peri-acid) on reduction. It has the constitution ... 

Neville-Winter acid peri acid R acid... 

Amino-8-naphthalene sulfonate 1-Aminonaphthaiene-8-sulfonic xid 8-Aminonaphthalene-1-sulphonic acid 8-Amino-1-naphthalenesulfonic acid EINECS 201-437-1 Naphthylaminemonosulfonic acid S a-Naphthylamine-8-sulfonic acid 1-Naphthalenesulfonic acid, 8-amino- 1-Naphthylamine-8-sulfonic xid NSC 7798 peri Acid. Used in the manufacture of dyestuffs as an azo dye intermediate. Soluble in H2O (20 mg/100 ml at 20 , 416 mg/100 ml at 100 ), freely soluble in AcOH, Kalpana Chemicals M/s. Textile Colour and Chemical (Exporfs). 

An explosion took the 25 mm thick cast-iron top off a peri-acid batch nitration vessel. Nobody was hurt, but the damage near to the vessel was substantial. No venting had been installed because of the expense, as production was scheduled to cease within five years. 

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