Synthesis of 3-hydroxy-5-per(poly)fluoroalkyl pyrazoles
摘要:
Treatment of ethyl alpha-per(poly)fluoroalkyl acetates 1 or ethyl alpha-iodo-beta-per(poly) fluoroalkyl acrylates 2 with hydrazine gives 3-hydroxy-5-per(poly)fluoroalkyl pyrazoles 3 in excellent yield. The effect of halogens on the pert polyfluoroalkyl chain and the reaction conditions were studied.
Synthesis of 2-Substituted 6-Fluoroalkylpyrimidin-4(3H)-ones and -pyrimidines
作者:Hui-Ping Guan、Qiao-Sheng Hu、Chang-Ming Hu
DOI:10.1055/s-1996-4327
日期:1996.8
Treatment of ethyl α-fluoroalkylacetates 1 or ethyl 3-fluoroalkyl-2-iodoacrylates 2 under mild conditions with amidine affords 2-substituted 6-fluoroalkylpyrimidin-4(3H)-ones 4, 5, 6, 7 in excellent yields, while α-fluoroalkyl alkyl ketones or α-fluoroalkyl aldehyde 3 give polysubstituted 6-fluoroalkylpyrimidines 8, 9 under the same conditions.
A convenient synthesis of 2-(F-alkyl)-4-hydroxyquinolines [1]
作者:Huang Wei-Yuan、Liu Yan-Song、Lu Long
DOI:10.1016/s0022-1139(00)83977-9
日期:1994.2
A convenient new route to 2-(F-alkyl)-4-hydroxyquinolines has been developed. In the presence of triethylamine, treatment of ethyl 2,2-dihydropolyfluoroalkanoates with aromatic amines in acetonitrile at 70 °C led to a mixture of the corresponding enamines and imines, which was cyclized in polyphosphoric acid (PPA) at 170 °C to give 2-(F-alkyl)-4-hydroxyquinolines in good yield.
An Effective Synthesis of 2-Trifluoromethyl- or 2-(1,1-Difluoroalkyl)thiophenes
作者:Hui-Ping Guan、Bing-Hao Luo、Chang-Ming Hu
DOI:10.1055/s-1997-1204
日期:1997.4
Various thiophenecarboxylates carrying a 2-trifluoromethyl, 2-(1,1-difluoroalkyl) or 2-polyfluoroalkyl group are synthesized conveniently from reaction of α-fluoroalkyl ketones 1, aldehydes 2 or ethyl α-fluoroalkylacetates 3 with methyl (or ethyl) 2-sulfanylacetates 4. A possible reaction pathway is suggested.
Reaction of Active Methylene Compounds with α-Fluoroalkyl Ketones or Esters: A Convenient Synthesis of 4-Trifluoromethylpyridines and meta-Trifluoromethylphenols
作者:Hui-Ping Guan、Chang-Ming Hu
DOI:10.1055/s-1996-4393
日期:1996.11
The reaction of α-fluoroalkyl ketones 1 or ethyl α-fluoroalkylacetates 2 with active methylene compounds such as methyl acetoacetate (3), acetylacetone (4) and diethyl malonate (5) produced unsaturated fluoroalkyl-containing 1,5-dicarbonyl compounds 6, from which polyalkyl-substituted 4-trifluoromethylpyridines 7, 4-trifluoromethylpryrid-2(1H)-ones 8 and meta-trifluoromethylphenols 9 were synthesized conveniently.
Aromatic annelation I. A versatile two-step synthesis of para-fluoroalkyl pyridines
作者:Hui-Ping Guan、Chang-Ming Hu
DOI:10.1016/0022-1139(95)03408-0
日期:1996.5
Polysubstituted para-fluoroalkyl pyridines and pyridones were prepared conveniently through reaction of α-fluoroalkyl-carbonyl compounds 1 and −1,3-dicarbonyl compounds 2, followed by treatment with ammonium hydroxide or ammonium acetate.