Nitropyrazoles 16. The use of methoxymethyl group as a protecting group for the synthesis of 4-methyl-3-nitro-5-R-pyrazoles
作者:A. A. Zaitsev、I. O. Kortusov、I. L. Dalinger、V. V. Kachala、G. P. Popova、S. A. Shevelev
DOI:10.1007/s11172-009-0289-7
日期:2009.10
4-methyl-3,5-dinitro-1-(3-oxobutyl)pyrazole results only in the removal of 1-protecting group and the formation of 2-[(3-oxobutyl)thio]acetanilide, while the action of anionic S-nucleophiles on 1-methoxymethyl-4-methyl-3,5-dinitropyrazole leads to the substitution products of the 5-NO2 group in which the methoxymethyl group can be removed by acid hydrolysis.
摘要 由 1,4-二甲基吡唑硝化制备的 4-甲基-3,5-二硝基吡唑在乙腈中在乙腈中容易与甲氧基甲基氯和甲基乙烯基酮反应,得到 1-甲氧基甲基-4-甲基-3,5-二硝基吡唑和分别为 4-甲基-3,5-二硝基-1-(3-氧代丁基)吡唑。巯基乙醇胺阴离子对 4-甲基-3,5-二硝基-1-(3-氧代丁基)吡唑的作用仅导致 1-保护基团的去除和 2-[(3-氧代丁基)硫代]乙酰苯胺的形成,而阴离子 S-亲核试剂对 1-甲氧基甲基-4-甲基-3,5-二硝基吡唑的作用导致 5-NO2 基团的取代产物,其中甲氧基甲基可以通过酸水解去除。