A facile synthesis of fluoroalkylated chromones and their analogues from 2,2-dihydropolyfluoroalkanoates
摘要:
Fluoroalkylated chromones and their analogues have been prepared in good yield by the Michael addition reactions of 2,2-dihydropolyfluoroalkanoates with phenols in the presence of triethylamine, followed by acid-catalyzed intramolecular ring-closure.
A convenient synthesis of polyfluoroalkyl-substituted pyrazolo[1,5-a] pyridine, pyrrolo[1,2-b]pyridazine and indolizine derivatives
作者:Xue-chun Zhang、Wei-yuan Huang
DOI:10.1016/s0022-1139(97)00118-8
日期:1998.1
(1b) or N-amino-isoquinolinium iodide (1c), N-phenacylpyridazinium (4), N-phenacylpyridinium (6a–c), and N-phenacylisoquinolinium (6d) bromides in DMF to give poly(per)fluoroalkyl-substituted pyrazolo[1,5-a] pyridine (3), pyrrolo[l,2-a]pyridazine (5) and indolizine (7 and 8) derivatives, respectively.
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.
A new approach to pyrrolo[1,2-a]quinoxaline derivatives
作者:Xue-chun Zhang、Wei-yuan Huang
DOI:10.1016/s0040-4039(97)01021-6
日期:1997.7
2-dihydropoly(per)fluoroalkanoate(2) reacted with N-phenacyl benzimidazole bromide(1a–1b),N-acetonyl benzimidazole bromide(1c) and N-ethoxycarbonylmethyl benzimidazole bromide(1d) in DMF to give pyrrolo[1,2-a]quinoxaline derivatives(3ae-3dg) respectively.
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.