O-Pyrazolylpropynyl-Hydroxylamines as Versatile Intermediates in the Synthesis of Compounds of Pharmacological Interest
作者:Mariá Isabel Rodríguez-Franco、Isabel Dorronsoro、Ana Martínez
DOI:10.1055/s-2001-16768
日期:——
Through an optimised Pd/Cu-catalysed cross-coupling reaction of 4-iodopyrazoles with 2-propyn-1-ol, followed by Mitsunobu transformation with N-hydroxyphthalimide and subsequent hydrazinolysis, O-[(pyrazol-4-yl)-prop-2-ynyl]-hydroxylamines were obtained in good yields. Their usefulness as intermediates in the synthesis of pharmaceuticals is exemplified by the first reported intramolecular cyclization of O-(2-propynyl)-hydroxylamines to yield 4,5-dihydro-isoxazoles.
通过优化Pd/Cu催化的4-碘吡唑与2-丙炔-1-醇的交叉耦合反应,随后进行 Mitsunobu 转化与 N-羟基邻苯二甲酰亚胺反应,并经后续肼解,以良好产率得到了O-[(吡唑-4-基)-丙-2-炔基]-羟胺。这些化合物作为药物合成中间体的实用性,通过首次报道的 O-(2-丙炔基)-羟胺的分子内环化反应生成4,5-二氢异噁唑得以体现。