A method for increasing the solubility of industrial azo pigments for 13C and 1H NMR spectra and the assignments of their 13C and 1H NMR peaks. (15th February 2021)

• Record Type: Journal Article
• Authors: Zhu, Meiling; Feng, Guangyuan; Lv, Dongjun; Qin, Nan; Li, Chunbao
• Is Part Of: Magnetic resonance in chemistry. Volume 59:Number 8(2021)
• Page Start: 804
• Page End: 814
• Publication Date: 2021-02-15
• Subjects: azo pigment -- DBU -- dimensional NMR -- peak assignment -- solubility -- solution 13C NMR; Nuclear magnetic resonance spectroscopy -- Periodicals; Chemistry, Organic -- Periodicals; Magnetic resonance -- Periodicals; 538.36
• DOI: 10.1002/mrc.5138
• Languages: English
• ISSNs: 0749-1581

Abstract

Abstract: A method for increasing the solubilities of industrial azo pigments in DMSO by adding DBU (1, 8‐diaza‐7‐bicyclo[5.4.0]undecene) has been developed. This facilitated the acquisition of solution 13 C NMR spectra of the pigments. This method was applied to four types of azo pigments: naphthol AS (3‐hydroxy‐2‐naphthoic acid anilide) pigments, naphthol pigments, pyrazolone pigments and acetoacetanilide pigments. This represents the first solution 13 C NMR spectra for naphthol AS pigments. Altogether 18 industrial azo pigments were analysed using 1D and 2D NMR techniques. The proton and corresponding carbon NMR resonances of these pigments have all been assigned. Abstract : The first solution 13 C NMR data of naphthol AS pigments are reported. 13 C NMR peaks of 18 industrial azo pigments were assigned based on 1D and 2D NMR.