68301-11-1Relevant academic research and scientific papers
Synthesis of multi-substituted 1,2,4-triazoles utilising the ambiphilic reactivity of hydrazones
Matsuzaki, Haruo,Takeda, Norihiko,Yasui, Motohiro,Okazaki, Mayuko,Suzuki, Seishin,Ueda, Masafumi
supporting information, p. 12187 - 12190 (2021/11/30)
The synthesis of N-alkyl-1H-1,2,4-triazoles from N,N-dialkylhydrazones and nitriles via formal [3+2] cycloaddition including the C-chlorination/nucleophilic addition/cyclisation/dealkylation sequence was developed. This sequential reaction utilising the in situ generation of hydrazonoyl chloride based on the ambiphilic reactivity of hydrazones afforded a variety of multi-substituted N-alkyl-triazoles in high yields. The synthetic utility of multi-substituted triazoles was also demonstrated by further transformations.
Photoinduced molecular rearrangements. The photochemistry of some 1,2,4-oxadiazoles in the presence of nitrogen nucleophiles. Formation of 1,2,4-triazoles, indazoles, and benzimidazoles
Buscemi, Silvestre,Vivona, Nicolo,Caronna, Tullio
, p. 8397 - 8401 (2007/10/03)
The photochemistry of some 3,5-disubstituted 1,2,4-oxadiazoles in the presence of nitrogen nucleophiles [external, such as added amines or hydrazines, or internal, such as an o-aminophenyl moiety at C(3) of the oxadiazole ring] has been investigated. In the irradiation of 5-amino-(or 5-N-substituted amino) 3-phenyl-1,2,4-oxadiazoles in the presence of aliphatic primary amines (or ammonia), photolytic species arising from heterolytic cleavage of the ring O-N bond capture the nucleophilic reagent to give open-chain intermediates, which develop into 1,2,4-triazolin-5-ones. Similarly, irradiations of 3,5-diphenyl-, 3-methoxy-5-phenyl-, and 5-methyl-3-phenyl-1,2,4-oxadiazoles gave 1,2,4-triazoles. In the same context, irradiations of representative substrates in the presence of hydrazines have been also investigated. In the irradiation of 3-(o-aminophenyl)-5-methyl-, 3-[o-(methylamino)phenyl]-5-methyl-, and 3-(o-aminophenyl)-5-phenyl-1,2,4-oxadiazoles, concomitant formation of indazoles and benzimidazoles, presumably arising from a common photolytic species, has been observed. Some mechanistic aspects have been considered, and possible applications in synthesis have been pointed out.
Regiospecific syntheses of the monomethylated 3-phenyldihydro-1,2,4-triazin-6(1H)-ones
Collins, David J.,Hughes, Timothy C.,Johnson, Wynona M.
, p. 463 - 468 (2007/10/03)
Unambiguous syntheses of four unreported monomethylated derivatives of 3-phenyldiliydro-1,2,4-triazin-6(1H)-ones, namely, the 1-methyl (2), 2-methyl (3), 4-methyl (4) and the imidic O-methyl derivative (5), are described. Regioselectivity was achieved for
SYNTHESIS AND STRUCTURE OF 1-METHYL-2,3-DIHYDRO-1,2,4-TRIAZOLIUM SALTS AND THEIR FREE BASES
Pinson, V. V.,Khrustalev, V. A.,Zelenin, K. N.,Matveeva, Z. M.
, p. 1170 - 1176 (2007/10/02)
1-Methyl-2,3-dihydro-1,2,4-triazolium iodides can be obtained by reacting methylhydrazones with S-methylthioamide hydriodides, by condensing 2-methylamidrazone hydriodides with aldehydes and ketones, or by reacting methyl iodide with 1-alkylidene(or arylidene)benzamidrazones.In solutions these salts are capable of undergoing tautomerism to 1-alkylidene(or arylidene)-2-methylamidrazone hydriodides.The influence of the structural factors on the position of the tautomeric equilibrium has been studied.The free bases obtained by neutralization of the respective salts by an alkali metal hydroxides are heretofore underscribed 1-alkylidene(or a rylidene)-2-methylhydrazidoimines or 4-triazolines, depending on their structure.Under the action of oxygen, these compounds are readily oxidized to substituted 1-methyl-1,2,4-triazoles with heating.
N-Methyl-N-(phenylsulfonyl)benzohydrazonoyl Chloride as a Potential Intermediate for Nitrogen-heterocycles. Preparation of 1-Methyl-3-phenyl-1H-1,2,4-triazoles and -pyrazoles
Ito, Suketaka,Tanaka, Yumo,Kakehi, Akikazu,Fukuyama, Toshihiko,Osawa, Nobuo,Sayo, Noboru
, p. 545 - 548 (2007/10/02)
3,5-Disubstituted 1-methyl-1H-1,2,4-triazoles and -pyrazoles were obtained in good to moderate yields by the reaction of N-methyl-N-(phenylsulfonyl)benzohydrazonoyl chloride with nitriles and with acetylenes in the presence of aluminum chloride.The triazo
