4818-39-7Relevant academic research and scientific papers
TBAI or KI-Promoted Oxidative Coupling of Enamines and N-Tosylhydrazine: An Unconventional Method toward 1,5- and 1,4,5-Substituted 1,2,3-Triazoles
Huang, Wei,Zhu, Chuanle,Li, Minke,Yu, Yue,Wu, Wanqing,Tu, Zhengchao,Jiang, Huanfeng
supporting information, p. 3117 - 3123 (2018/08/01)
A novel method for the synthesis of 1,5- and 1,4,5-substituted 1,2,3-triazoles has been reported. This approach is promoted by iodine-TBHP oxidation system using enamines and N-tosylhydrazine as materials, which avoid the dependence of traditional methods on azides and transition metals. Through this approach, various 1,5- and 1,4,5-substituted 1,2,3-triazoles were delivered in moderate to high yields. The mechanistic study indicated that an amino exchange would be involved in the reaction process. Moreover, the product methyl 1-(2-methoxyphenyl)-4-methyl-1H-1,2,3-triazole-5-carboxylate is a useful precursor to anti-influenza A agent, and further application research was conducted. (Figure presented.).
Transition-metal-free synthesis of β-trifluoromethylated enamines with trifluoromethanesulfinate
Jiang, Huanfeng,Huang, Wei,Yu, Yue,Yi, Songjian,Li, Jiawei,Wu, Wanqing
supporting information, p. 7473 - 7476 (2017/07/12)
We have developed a transition-metal free trifluoromethylation protocol between enamines and CF3SO2Na. A wide range of β-trifluoromethyl substituted enamines were delivered in moderate to high yields with only E-configurations.
Cyanoacetaldehyde - New Synthetic Applications of an Old Compound Syntheses with Nitriles, XCI
Jachak, Madhukar,Kriessmann, Ulrike,Mittelbach, Martin,Junek, Hans
, p. 199 - 208 (2007/10/02)
Various reactions of cyanoacetaldehyde (1), freshly prepared by ozonization of (E)-1,4-dicyano-2-butene or allylcyanide, are described.Thus, conversion of 1 with anilines gave β-phenylaminoacrylonitriles 2a-e.Reaction of 1 with hydrazines led to the corresponding hydrazones 3a-e, which could be cyclized under alkaline conditions to 5-aminopyrazoles 4a-d.An aldol-type condensation product 5a could be obtained by reaction of 1 with sodiumphenoxide.Treatment of 1 with dimethylformamide-dimethylacetal led to the formation of (E)-3-dimethylamino-2-formylpropenenitrile (6), a very useful synthon in synthetic chemistry.For the determination of the structure of 6 the method of steady state diffferential NOEs was used.Reaction of 6 with hydrazines gave 1-substituted-4-cyanopyrazoles 7a-k. Keywords.Cyanoacetaldehyde; Hydrazones; Cyanopyrazoles; Aminopyrazoles.
Influence of N-substitution in the FVT of pyrazoles
Perez, Jorge D.,Yranzo, Gloria I.,Phagouape, Leonardo M.
, p. 129 - 132 (2007/10/02)
Flash vacuum thermolysis of 1-ethyl (3), 3,5-dimethyl-1-ethyl (4), 1-n-buthyl (5), 1-tert-butyl (6), 3,5-dimethyl-1-phenyl (7) and 1-phenyl-pyrazole (8) was studied.In the N-alkyl derivatives, pyrazole elimination and olefin formation was found.In contrast, phenylderivatives afforded isomerization and nitrogen extrusion.Kinetic parameters for compound 4 are described and a general mechanism including the N-H derivatives is discussed.
