NOE difference spectroscopy as a versatile tool for spectral and structural assignment in various N-1 substituted pyrazoles was written by Holzer, Wolfgang. And the article was included in Tetrahedron in 1991.HPLC of Formula: 54210-32-1 This article mentions the following:
NOE difference spectroscopy is proposed as a simple method for the discrimination between pyrazole H-3 and H-5 resonances in various 1-substituted and 1,4-disubstituted pyrazoles as well as for the differentiation between isomeric pairs of 1,3,4- and 1,4,5-trisubstituted, or 1,3- and 1,5-disubstituted pyrazoles, utilizing a through-space connection between a pyrazole H-5 proton and protons of the N-1 substituent. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1HPLC of Formula: 54210-32-1).
1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1) belongs to pyrazole derivatives. An alternative way to synthesize multisubstituted pyrazoles is the Csingle bondH arylation of simple pyrazoles. Protonation of pyrazole in strong acid leads to pyrazolium cations, which undergo electrophilic substitution preferentially at C3 rather than C4. The pyrazole anion is not reactive toward nucleophiles but is mostly reactive to electrophiles.HPLC of Formula: 54210-32-1
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics