Hydrazones

Conclusions On the basis of the results of IR spectroscopy and of a comparison between the theoretical and experimental values of the dipole moments, the authors show that the benzoylhydrazones of aromatic aldehydes in crystals and solutions exist in the form of an equilibrium mixture of two rotational forms (EEE and EEE) or the syn-isomer, due to difficulty of rotation about the N-CO amide bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 559–565, March, 1976.     

Hydrazones

Conclusions The electrochemical reduction of a number of symmetrically and nonsymmetrically substituted benzalazines on a mercury electrode in dimethylformamide was studied by the methods of classical, switched, and cyclic polarography as well as microelectrolysis.A continuation of the series, Study of the Structure and Eeactivity of Nitrogen-Containing Derivatives of Carbonyl Compounds [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2179–2183, October, 1972.     

Hydrazones

The products of the reaction of 1-chloro- and 1,4-chlorophthalazines with hydrazine are the E isomers of the hydrazones of the corresponding phthalazone rather than hydrazinophthalazines, as previously assumed. The hydrazones of 2-methylphtalazones exist in the Z form.See [1] for communication XXXIX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 402–409, March, 1976.     

Hydrazones

The polarographic behavior of a number of N-benzylideneiminopyridinium iodides in aqueous alcohol buffer solutions was studied over a wide range of pH values. The mechanism of their reduction on a dropping mercury electrode and the factors affecting the cleavage of the N-N bond are discussed. The reduction product-the pyridinium ion-induces the catalytic evolution of hydrogen.     

Synthesis and Properties of Glass-Forming Hydrazones II [1]. Hydrazones Containing Bicarbazolyl Units

 A series of new glass-forming hydrazones containing bicarbazolyl units were synthesized starting from 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole and 9-(6-(9H-carbazol-9-yl)-hexyl)-9H-carbazole, and their thermal properties were studied. The correlation between their inclination to form glasses and their chemical structures are discussed. The results of a preliminary investigation of the photoelectric properties of amorphous films of the title compounds are briefly reported. The highest hole drift mobility was observed for 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole-3-carbaldehyde N,N-diphenylhydrazone; at high electric fields, it approaches 1 · 10⁻³ cm²/Vs.     

Synthesis and Properties of Glass-Forming Hydrazones II [1]. Hydrazones Containing Bicarbazolyl Units

Summary.  A series of new glass-forming hydrazones containing bicarbazolyl units were synthesized starting from 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole and 9-(6-(9H-carbazol-9-yl)-hexyl)-9H-carbazole, and their thermal properties were studied. The correlation between their inclination to form glasses and their chemical structures are discussed. The results of a preliminary investigation of the photoelectric properties of amorphous films of the title compounds are briefly reported. The highest hole drift mobility was observed for 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole-3-carbaldehyde N,N-diphenylhydrazone; at high electric fields, it approaches 1 · 10⁻³ cm²/Vs. Received September 17, 2001. Accepted (revised) October 16, 2001     

Synthesis of Novel Saccharide Hydrazones

Synthesis of important heterocyclic hydrazine derivatives N-aminopyrrolidine, N-aminopiperidine, and N-aminoazepane from hydrazine hydrate and dihalogenides were examined and optimized. These heterocyclic hydrazine derivatives were used in condensation reactions with six different monosaccharides to form corresponding hydrazones. Biological evaluations of these novel compounds, which are simple acyclic nucleoside analogs, were done. L-Arabinose N-aminoazepane hydrazone showed minor anti-HIV activity, giving a starting point for further structural modifications.     

One-Pot Synthesis of N-Alkyl Sulfonyl Hydrazones by Dialkyl Acetylenedicarboxylate-Mediated Reaction of Trialkylphosphites with Sulfonyl Hydrazones

Stable derivatives of N-alkyl sulfonyl hydrazone were obtained in excellent yields from the reaction between electron-deficient acetylenic ester compounds and sulfonyl hydrazones in the presence of trialkylphosphites in dichloromethan at room temperature.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

苯乙酮类去氢枞酰腙的合成

以去氢枞酸为原料,经三氯化磷酰氯化得到去氢枞酰氯(2);2与85%水合肼反应合成了去氢枞酰肼(3);3再分别与苯乙酮及其衍生物发生缩合反应得到4个新型的苯乙酮类去氢枞酰腙化合物,其结构经UV,1H NMR和IR表征.     

Synthesis of Branched Hydrazones by Reaction of N-(2,3-Epoxypropyl) Derivatives of Hydrazones with Benzenediols

A series of branched hydrazones have been prepared by reaction of N-(2,3-epoxypropyl) derivatives of 9-ethyl-3-carbazolecarbaldehyde and 4-diethylamino-benzcarbaldehyde phenylhydrazones with 1,2-, 1,3-, and 1,4-benzenediols. It was found that the reaction rate depends on the polarity of solvents.     

Synthesis and Characterization of Acetone Hydrazones

1‐Isopropylidene‐2‐methylhydrazine ( 1 ), 1‐isopropylidene‐2‐hydroxyethylhydrazine ( 2 ) and 1‐isopropylidene‐2‐formylhydrazine ( 3 ) were synthesized by reaction of the corresponding hydrazine with an excess of acetone in the presence of a drying agent (anhydrous sodium sulfate or barium oxide). All compounds 1 – 3 were characterized by elemental analysis, coupled gas chromatography‐mass spectrometry (GC–MS), multinuclear NMR spectroscopy (¹H, ¹³C and ¹⁵N) and vibrational spectroscopy (infrared and Raman). Compounds 1 and 2 are liquid at room conditions and their density was measured by means of a picnometer, however, (at room conditions) compound 3 is a solid and its crystal density and structure were determined by low temperature X‐ray diffraction techniques (monoclinic, P2₁/n, Z = 4, a = 5.666(1) Å, b = 6.254(1) Å, c = 15.277(4) Å, β = 91.30(2)°, V = 541.2(2) ų). The structure of hydrazone 3 is discussed in detail and compared to that of monoformylhydrazine. Finally, the (gas phase) structure of compound 3 was optimized using DFT calculations (B3LYP/6‐31+G(d, p)) and its NBO charges are reported.     

Hydrazones as analytical reagents: a review

Applications of hydrazones in inorganic analysis since 1950 are reviewed.     

Structural and Spectroscopic Properties of Benzoylpyridine-Based Hydrazones

Photochromic hydrazones are attracting the attention in the field of photochromic systems especially due to their P-type character. To understand the structural features and their correlation with the spectroscopic data, UV-Vis, vibrational and ellipsometry spectroscopic techniques are employed with the support of density functional theory (DFT) calculations to three hydrazone derivatives based on benzoylpyridine. Interestingly, analysis of the structure shows the presence of two distinct rotamers around the pyridine ring with different energy and the well-defined conjugation path that changes due to E to Z isomerization especially in the hydrazone −C=N−NH part of the skeleton. IR and Raman spectra are analyzed, showing a higher selectivity in the Z form; moreover, the comparison with the normal modes proves the effect of the reaction on the backbone structure. The experimental results are in good agreement with the theoretical predictions, especially in the case of the Raman spectrum. The molecular polarization also changes from E to Z forms as predicted by DFT calculations. Spectroscopic ellipsometry on thin films of TOPAS doped with 10 %wt of the dimethylamino hydrazone derivative is used to prove such change at the molecular level. A modulation of the refractive index is observed, and it is correlated with the concentration of the active moiety and the calculated electronic polarizabilities.     

Synthesis and Characterization of Benzenesulfonyl Hydrazones and Benzenesulfonamides

In the search for structural cyclic imide analogues of therapeutic interest, the syntheses and characterization of benzenesulfonyl hydrazones and benzenesulfonamides are described. The benzenesulfonyl chlorides (2) and (3) were obtained through the Diels–Alder reaction between N‐p‐chloro‐sulfonylfenylmaleimide (1) and furan or 2‐methylfuran. The reactions of (2) and (3) with hydrazine and amines afforded the hydrazides and sulfonamides, respectively. The sulfonylhydrazones were obtained through a condensation between the sulfonylhydrazides with different benzaldehydes.