Synthesis and some properties of 6-di(tri)fluoromethyl-and 5-di(tri)fluoroacetyl-3-methyl-1-phenylpyrano[2,3-c]pyrazol-4(1H)-ones
作者:V. Ya. Sosnovskikh、M. A. Barabanov、B. I. Usachev、R. A. Irgashev、V. S. Moshkin
DOI:10.1007/s11172-006-0199-x
日期:2005.12
Condensation of 4-acetyl-5-hydroxy-3-methyl-1-phenylpyrazole with RFCO2Et (RF = CF2H, CF3) in the presence of LiH affords 4-di(tri)fluoroacetoacetyl-5-hydroxy-3-methyl-1-phenylpyrazoles from which 6-di(tri)fluoromethyl-and 5-di(tri)fluoroacetyl-3-methyl-1-phenylpyrano[2,3-c]pyrazol-4(1H)-ones were synthesized. The reactions of pyrano-pyrazoles with hydrazine hydrate, ethyl mercaptoacetate, or aromatic amines proceed at the C(6) atom with pyrone ring opening and formation of aminoenones, pyrazoles, or thiophenes with the 5-hydroxy-3-methyl-1-phenyl-4-pyrazolyl fragment.
在 LiH 存在下,4-乙酰基-5-羟基-3-甲基-1-苯基吡唑与 RFCO2Et(RF = CF2H、CF3)在 LiH 存在下缩合得到 4-二(三)氟乙酰基-5-羟基-3-甲基-1-苯基吡唑,并由此合成了 6-二(三)氟甲基和 5-二(三)氟乙酰基-3-甲基-1-苯基吡喃并[2,3-c]吡唑-4(1H)-酮。吡喃并吡唑与水合肼、巯基乙酸乙酯或芳香胺的反应在 C(6)原子上进行,吡喃酮环打开,并与 5-羟基-3-甲基-1-苯基-4-吡唑片段形成氨基烯酮、吡唑或噻吩。