Nitropyrazoles: XII. Transformations of the 4-Methyl Group in 1,4-Dimethyl-3,5-dinitropyrazole and Cyclization of the Transformation Products
作者:A. A. Zaitsev、I. L. Dalinger、A. M. Starosotnikov、V. V. Kachala、Yu. A. Strelenko、T. K. Shkineva、S. A. Shevelev
DOI:10.1007/s11178-005-0374-9
日期:2005.10
A preparative procedure for the synthesis of 1,4-dimethyl-3,5-dinitropyrazole by nitration of 1,4-dimethylpyrazole was developed. The reaction of 1,4-dimethyl-3,5-dinitropyrazole with dimethoxymethyl- (dimethyl)amine (N,N-dimethylformamide dimethyl acetal) gave (E)-N,N-dimethyl-2-(1-methyl-3,5-dinitropyrazol- 4-yl)ethenylamine. Acid hydrolysis of the latter afforded (1-methyl-3,5-dinitropyrazol-4-yl)acetaldehyde, and the reaction with sodium nitrite in hydrochloric acid led to formation of 2-hydroxymino-2-(1-methyl- 3,5-dinitropyrazol-4-yl)acetaldehyde. The corresponding O-methyloxime and phenylhydrazone reacted with K2CO3 to give 6-methyl-4-nitropyrazolo[4,3-d]isoxazole-3-carbaldehyde O-methyloxime and 1-methyl-3-nitro-4-(2-phenyl-2H-1,2,3-triazol-4-yl)pyrazol-5-ol, respectively. Treatment of (1-methyl-3,5-dinitropyrazol-4-yl)-acetaldehyde with benzenediazonium chloride gave (1-methyl-3,5-dinitropyrazol-4-yl)acetaldehyde phenylhydrazone which underwent intramolecular cyclization with replacement of the 5-nitro group by the action of K2CO3 in acetonitrile; in the reaction with K2CO3 in ethanol, the 5-nitro group was replaced by ethoxy.
开发了一种通过硝化1,4-二甲基吡唑合成1,4-二甲基-3,5-二硝基吡唑的预处理方法。1,4-二甲基-3,5-二硝基吡唑与二甲氧基甲基(二甲基)胺(N,N-二甲基甲酰胺二甲基乙缩醛)反应生成(E)-N,N-二甲基-2-(1-甲基-3,5-二硝基吡唑-4-基)乙烯胺。后者的酸水解产物为(1-甲基-3,5-二硝基吡唑-4-基)乙醛,与盐酸中的亚硝酸钠反应生成2-羟亚氨基-2-(1-甲基-3,5-二硝基吡唑-4-基)乙醛。相应的O-甲基肟和苯腙与K2CO3反应分别生成6-甲基-4-硝基吡唑并[4,3-d]异恶唑-3-醛O-甲基肟和1-甲基-3-硝基-4-(2-苯基-2H-1,2,3-三唑-4-基)吡唑-5-醇。(1-甲基-3,5-二硝基吡唑-4-基)乙醛与苯重氮氯化物反应生成(1-甲基-3,5-二硝基吡唑-4-基)乙醛苯腙,该化合物在乙腈中与K2CO3反应,5-硝基被取代并发生分子内环化;在乙醇中与K2CO3反应,5-硝基被取代为乙氧基。