New Intermediates and Dyes for Synthetic‐polymer Fibres. Benzimidazothioxanthenoisoquinolinone Dioxides and Sulphones of 7H‐Benzimidazo (2, 1‐a) benz(d, e) isoquinolin‐7‐one

Abstract

Condensation of benzo(k,i)thioxanthene‐3, 4‐dicarboxylic acid‐7, 7‐dioxide with o‐phenylenediamine gives a mixture of the new heterocycles benzimidazo(1, 2‐b) thioxantheno(2, 1, 9‐d, e, f) isoquinoline‐7‐one‐16, 16‐dioxide and benzimidazo(2, 1‐a) thioxantheno(2, 1, 9‐d, e, f) isoquinolin‐8‐one‐5, 5‐dioxide. Separation of these isomers is reported, together with their characterisation by unambiguous synthesis. Similar reaction with substituted o‐phenylenediamines affords other isomer mixes of the above. These new dyes colour polyester fibres in orange hues of excellent fastness to light and sublimation. Comparison of the dyes is made with the uncyclised sulphone derivatives of 7H‐benzimidazo(2, 1‐a) benz(d, e) isoquinoline‐7‐one, which are novel bright yellow dyes of good coloration and fastness properties on polyester.

Synthesis and Application of Some Alkali‐Clearable Azo Disperse Dyes Based on Naphthalimide Derivatives

“…In the UV range, there are only naphthalene bands, characteristic for simple naphthalene derivatives which are ascribed to the absorption of the benzeneazonaphthalene (BAN) chromophore and in the visible range bands characteristic for azo dyes. [14][15][16][17] The chromophore in the 340-375 nm range and in the visible range the K-band (p®p* shifts) appears in the region 500-589 nm, characteristic for azo dyes. 18 The present considerations are limited to a discussion of bands within 206-589 nm, where the known K and R bands (n®p* shifts) appear and show characteristic changes depending on the solvent used.…”