3-(多氟酰基)发色酮与羟胺游离碱的反应通过亲核的1,4-加成反应进行,随后打开吡喃环并随后环化为4-(多氟烷基)-4 H-苯并[3,4- d ]异恶唑- 4-醇收率良好。用三氟乙酸处理时,该环状杂环系统的异恶唑环打开,得到3-氰基-2-(聚氟烷基)色酮,将其成功地用浓H 2 SO 4水解,得到3-氨基甲酰基-2-(聚氟烷基)色酮。 。另一方面,用羟胺盐酸盐对3-(聚氟酰基)色酮进行肟化反应是在与R F基团相连的羰基碳原子上或在C-2原子上发生的,从而得到3-R F。C(NOH)-色酮和5-R F -4-水杨酸异恶唑肟。通过简单地在二甲基亚砜中加热,将前者容易地转化为3-R F -4-水杨酸异恶唑。
The selectivity of the reactions of 3-(polyfluoroacyl)-4H-chromen-4-ones with a wide range of aminoheterocycles and arylamines has been evaluated. The method described facilitates access to polyfluoroalkyl-containing fused pyridines. aminoheterocycles - arylamines - condensation - chroman-4-ones - polyfluoroalkyl - fused pyridines
2-Hydroxy-2-(polyhaloalkyl)chroman-4-ones react with diethoxymethyl acetate at 140-150 °C for 15 minutes to give 3-(polyhaloacyl)chromones in good yields. The reactions of these compounds with amines proceeds at C-2 with pyrone ring-opening and formation of 2-(alkyl/arylaminomethylene)-2-hydroxy-2-(polyfluoroalkyl)chroman-4-ones.
One-pot three-component reaction of 3-(polyfluoroacyl)chromones with active methylene compounds and ammonium acetate: regioselective synthesis of novel RF-containing nicotinic acid derivatives
作者:Vyacheslav Ya. Sosnovskikh、Roman A. Irgashev、Mikhail I. Kodess
DOI:10.1016/j.tet.2008.01.076
日期:2008.3
Reactions of 3-(polyfluoroacyl)chromones with acetoacetamide and ethyl acetoacetate in the presence of ammonium acetate proceed at the C-2 atom of the chromone system with pyrone ring-opening and subsequent cyclization to 5-salicyloyl-2-methyl-6-(trifluoromethyl)nicotinamides, ethyl 5-salicyloyl-2-methyl-6-(trifluoromethyl)nicotinates, and ethyl 5-hydroxy-2-methyl-5-(polyfluoroalkyl)-5H-chromeno[4
在乙酸铵存在下,3-(聚氟酰基)色酮与乙酰乙酰胺和乙酰乙酸乙酯的反应在色酮系统的C-2原子处进行,且吡喃酮开环,随后环化为5-水杨酰基-2-甲基-6-(三氟甲基)烟酰胺,5-水杨酰基-2-甲基-6-(三氟甲基)烟酸酯和乙基5-羟基-2-甲基-5-(多氟烷基)-5 H-苯并[4,3 - b ]吡啶-3 -羧酸盐。与β-aminocrotononitrile相似的反应,得到5-羟基-2-甲基-5-(多氟烷基)-5 ħ -chromeno [4,3- b ]吡啶-3-甲腈。
3-(Polyfluoroacyl)chromones and Their Hetero Analogues as Valuable Substrates for Syntheses of 4-(Polyfluoroalkyl)pyrimidines
Reactions of 3-(polyfluoroacyl)chromones and their hetero analogues with a number of 1,3-NCN-dinucleophiles, such as amidines or guanidines, were studied in detail, and preparative access to a set of diverse 5-salicyloyl-4-(polyfluoroalkyl)pyrimidines was elaborated. These compounds appear to be a suitable starting substrates for the synthesis of 4-(polyfluoroalkyl)pyrimidine-5-carboxylic acids or
A Novel and Convenient Synthesis of 3-(Polyhaloacyl)chromones Using Diethoxymethyl Acetate
作者:Vyacheslav Ya. Sosnovskikh、Roman A. Irgashev
DOI:10.1055/s-2005-865199
日期:——
The reaction of 2-hydroxy-2-(polyhaloalkyl)chroman-4-ones with diethoxymethyl acetate readily occurs at 140-150 °C for 15 minutes to give 3-(polyhaloacyl)chromones in good yields.