1-Methyl-1-(2,4-dinitrophenyl)hydrazine as a New Reagent for the HPLC Determination of Aldehydes

Abstract

The synthesis and first application of an N-alkylated hydrazine reagent for the HPLC determination of aldehydes and ketones is described. 1-Methyl-1-(2,4-dinitrophenyl)hydrazine (MDNPH) reacts with aldehydes to give the corresponding hydrazones in the presence of an acid as catalyst. In contrast to other hydrazine reagents, MDNPH is oxidized by both ozone and nitrogen dioxide quantitatively to N-methyl-2,4-dinitroaniline (MDNA), which can be separated from the hydrazones of the lower aldehydes by means of HPLC. Unexpected elution orders are observed for the 1-methyl-1-(2,4-dinitrophenyl)hydrazones compared to those of 2,4-dinitrophenylhydrazones. Dual-wavelength detection is employed as a means for identification of different groups of the hydrazones and MDNA.

Reply to a Comparison of Survival and Disease‐Specific Survival in Surgically Resected, Lymph Node‐Positive Bronchioloalveolar Carcinoma Versus Nonsmall Cell Lung Cancer: Implications for Adjuvant Therapy

“…Hydrazone group has a lower hydrophilic character than that of the protonated hydrazine decreasing the stabilization effect of the VBH monomer. Furthermore, hydrazones are weak bases, and they are not protonated even at very strong acid conditions 36. Increasing the pH from 1 to 3 and 7, higher conversions and number of particles were achieved because the masking of VBH with acetone is favored at an acid pH.…”

The preparation, spectroscopy, structure and electrochemistry of some [Co(η4-C4Ph4)(η5-C5H4CC–CHY)], [Fe(η5-C5H5)(η5-C5H4CC–CHY)], and related complexes

“…Previously reported procedures or closely related ones were used to prepare [Co(h 4 -C 4 Ph 4 )(h 5 -C 5 H 4 CHO)] 1a [16], [Fe(h 5 -C 5 H 5 )(h 5 -C 5 H 4 CHO)] 1b [21], [Fe(h 5 -C 5 H 5 )(h 5 -C 5 H 4 CH 2 PPh 3 )]I [22], [ClCH 2 PPh 3 ]Cl [23], 1-methyl-1-(2,4-dinitro-phenyl)hydrazine [24], and [Fe 2 (h 5 -C 5 H 5 ) 2 (CO) 2 (m-CO)(m-CCH 3 )][BF 4 ] [25]. Other reagents were purchased from commercial sources unless otherwise stated.…”

Experimental choices for the determination of carbonyl compounds in air

“…As Reduced reactivity compared to that of DNPH [40] HPLC -DAD N-Methyl-4-hydrazino-7-nitrobenzofuran Slightly higher absorption maxima than MDNPH and produce one defined product in reaction with O 3 and NO 2…”

“…Büldt and Karst [40] proposed the use of N-methyl-2,4-dinitrophenylhydrazine (MDNPH) which is subject to weak interferences. It is known to produce one defined product (N-methyl-2,4-dinitroaniline) in reaction with both O 3 and NO 2 , which may then easily be separated from the hydrazones of interest.…”