B S Joshi
Articles written in Proceedings – Section A
Volume 32 Issue 4 October 1950 pp 201-211
Indanthrene Turquoise Blue GK and 3GK have been shown to be 11-chloro-6-aminoanthraquinoneacridone (II) and 10∶12-dichloro-6-aminoanthraquinoneacridone (III) respectively by unambiguous synthesis. The absorption spectra of the commercial and the synthetic dyestuffs have been determined. Chloro derivatives of 6-aminoanthraquinoneacridone, substituted by chlorine in the anthraquinone nucleus, in the benzene half of the molecule, and in both the anthraquinone and the benzene halves, have been synthesised, and the fastness properties of the shades on cotton determined. 6-Aminoanthraquinoneacridone has been prepared by a new route; the various chloro derivatives of 6-aminoanthraquinoneacridone which have been synthesised are the 7-, 10-, and 11-monochloro, 7∶10-, 7∶11- and 10∶12-dichloro, the 7∶10∶12-trichloro and 11-chloro-7-bromo-compounds. It is found that the acridones containing a chlorine atom in the 7-position, adjacent to the amino group, are dehalogenated by treatment with aqueous alkali and hydrosulphite at room temparature (28°) for about one hour.
Volume 32 Issue 5 November 1950 pp 348-351
The constitution (I), assigned by Howard and Raistrick1 to islandicin, the coloring matter from the dried mycelium of
3-Nitro-2-(5′-benzeneazo-2′-hydroxy-4′-methyl)-benzoylbenzoic acid (VII), obtained by coupling 3-nitro-2-(2′-hydroxy-4′-methyl)-benzoylbenzoic acid (VI) with diazotized aniline, gave on reduction 3-amino-2-(5′-amino-2′-hydroxy-4′-methyl)-benzoylbenzoic acid (VIII). The latter was converted in one step to 1∶4∶5-trihydroxy-2-methylanthraquinone (I) by tetrazotization and treatment with hot sulphuric acid. The properties of (I), its triacetate and its trimethyl ether are identical with those of islandicin, its triacetate and its trimethyl ether described by Howard and Raistrick.
Volume 34 Issue 5 November 1951 pp 304-315
The synthesis of 4-chloro-, bromo- and iodo- alizarins is described. Bromination of 2-
Volume 38 Issue 6 December 1953 pp 474-479
1:3-Dichloroanthraquinone has been prepared by the deamination of 1-amino-2:4-dichloroanthraquinone. The dichloroanthraquinone is useful for the preparation of 1-amino-3-chloroanthraquinone.