International Journal of Interdisciplinary Research
Table 4 1 H-NMR chemical shift (ppm) of the purified Blue pigment
From: Extraction of Indigo dye from Couroupita guianensisand its application on cotton fabric
Peak no. | Position of1H | Chemical shift (ppm) | Comment |
|---|---|---|---|
1 | H-1 | 4.054 | Aromatic C-NH |
2 | H-5 | 8.486 | 1-benzene C-H |
3 | H-6 | 7.025 | 1-benzene C-H |
4 | H-7 | 7.458 | 1-benzene C-H |
5 | H-7′ | 7.458 | 1-benzene C-H |
6 | H-6′ | 7.025 | 1-benzene C-H |
7 | H-5′ | 8.473 | 1-benzene C-H |
8 | H-1′ | 4.054 | Aromatic C-NH |