1-(Phenylamino)Pseudo-Mauveine: A New Water Soluble Phenazine Dye

Abstract

1-(Phenylamino)pseudo-mauveine was prepared by the oxidation of 1,3,5-tris(phenylamino)benzene and p-phenylenediamine with potassium dichromate. The absorption maximum of 535 nm is shifted hypsochromically by about 20 nm compared to that for pseudo-mauveine. Condensation of 1,3,5-tris(phenylamino)benzene with 4-nitrosodiphenylamine under strongly acidic conditions gave 1,3,7-tris(phenylamino)-5-phenylphenazinium sulfate and 10-phenyl-6,8-bis(phenylamino)-2,10dihydrophenazin-2-one.

WH Perkin, Patent AD 1856 No 1984: A Review on Authentic Mauveine and Related Compounds

“…[14][15][16] By the turn of the century Nietzki established the structure of the chromophore to be that shown in compound 3, called pseudo-mauveine, by performing syntheses from pre-formed building blocks. [17][18] This is the best way to synthesise the chromophore in higher yields (Scheme 1). The dimer 5 16,18 and trimer 7 19 can also be used with aniline 6.…”

“…[17][18] This is the best way to synthesise the chromophore in higher yields (Scheme 1). The dimer 5 16,18 and trimer 7 19 can also be used with aniline 6. Perkin also reported the oxidation of pseudo-mauveine 3 to give pink safranin 8 which had been prepared by other methods (Scheme 2).…”

“…The provenance of authentic mauveine is still disputed, 11 30 CaOCl, 31 Cu(II)(NO 3 ) 2 or many other oxidants claimed in this patent. 32 Our studies have centred upon the preparation of derivatives similar to or related to those found in mauveine, 16,18,33 and upon the synthesis of mauveine that has the same composition as authentic mauveine. 20,34 Finally we performed a detailed study on the oxidation products of p-toluidine to verify early literature studies.…”

The Isolation of N-tert-Butyl-p-Toluidine Hydrochloride and the Synthesis of Mauveine

“…Previously we reported the synthesis of a mixture of mauveine A and mauveine B by the oxidation of a mixture of N-tertbutyl-p-toluidine, o-toluidine and aniline (1.0 : 1.5 : 1.8) with K 2 Cr 2 O 7 in dilute sulfuric acid 1 and related studies [2][3][4][5] (Scheme 1). The reaction favours the formation of mauveine A and mauveine B over other mauveine chromophores and the ratio of aniline to o-toluidine controls the ratio of mauveine A to mauveine B.…”

A Paddle-Wheel Motif versus an Extended Network: Two Crystalline Forms of 2,4-Bis(Phenylamino)Nitrobenzene

“…Our ongoing programme on the synthesis of mauveine derivatives [10][11][12][13][14] required some specialised aromatic building blocks, which we attempted to prepare by reacting 2,4-difluoronitrobenzene 1, with aniline (Scheme 1). The nitro group activates both fluorine substituents to nucleophilic displacement.…”