Materials and methods
All the employed chemicals were of analytical reagent grade.
The aromatic amines shown in Table 1 were used for diazotization.
Wool and silk fabrics were gifted by Color Tax
(Pvt) Ltd., Surat, India. Melting points were determined
by the open capillary method and are given uncorrected.
The UV visible absorption spectra were measured on a Carl
Zeiss UV/Vis Specord spectrometer, and the elemental analysis
was realized using a Perkin Elmer CHNS/O Analyzer
2400 Series II. The infrared spectra were recorded in KBr
pellets on a Perkin–Elmer Spectrum GX FT-IR model.
The 1H-NMR spectra were recorded on Hitachi R-1500
(400 MHz) in DMSO-d6 solvent and thin layer chromatography
(TLC) was run on aluminium sheets pre-coated with silica
gel 60 F254 (Merck, Germany) using a
methanol:water:acetic acid (12:3:7) solvent system. The color
spots were visualized by a UV cabinet. A HTHP dyeing
machine (model LL) was used for dyeing.