Efficient Synthesis of Nitroflavones by Cyclodehydrogenation of 2′-Hydroxychalcones and by the Baker-Venkataraman Method
摘要:
Several nitroflavone derivatives were synthesized by cyclodehydrogenation of 2'-hydroxychalcones and by the Baker-Venkataraman approach, starting from 2'-hydroxyacetophenones and benzoic acid derivatives. Nitroflavones synthesised by the first synthetic approach were obtained in better global yields than those obtained by the later method. The structures of all new compounds were elucidated by microanalyses, 1D and 2D NMR, IR, and mass spectroscopic measurements.
Efficient Synthesis of Nitroflavones by Cyclodehydrogenation of 2′-Hydroxychalcones and by the Baker-Venkataraman Method
摘要:
Several nitroflavone derivatives were synthesized by cyclodehydrogenation of 2'-hydroxychalcones and by the Baker-Venkataraman approach, starting from 2'-hydroxyacetophenones and benzoic acid derivatives. Nitroflavones synthesised by the first synthetic approach were obtained in better global yields than those obtained by the later method. The structures of all new compounds were elucidated by microanalyses, 1D and 2D NMR, IR, and mass spectroscopic measurements.
One-pot synthesis of 2-(2-hydroxyaryl)quinolines: reductive coupling reactions of 2′-hydroxy-2-nitrochalcones
作者:Ana I.R.N.A Barros、Artur M.S Silva
DOI:10.1016/s0040-4039(03)01374-1
日期:2003.7
A one-pot synthesis of novel 2-(2-hydroxyaryl)quinolines have been developed from the intramolecular reductivecouplingreactions of 2′-hydroxy-2-nitrochalcones, induced by stannous chloride in acidic medium (HCl/AcOH). In some cases these transformations can be performed with ammonium formate/Pd–C in methanol.
Reductive Coupling Reactions of 2-Nitrochalcones and their β-Hydroxy-analogues: New Syntheses of 2-Arylquinoline and 2-Aryl-4-hydroxyquinoline Derivatives
作者:Ana I. R. N. A. Barros、André F. R. Dias、Artur M. S. Silva
DOI:10.1007/s00706-007-0647-9
日期:2007.6
A one-pot synthesis of novel 2-arylquinolines and 2-aryl-4-hydroxyquinolines was developed from the intramolecular reductive coupling reactions of 2-nitrochalcones and 3-hydroxy-1-phenyl-3-(2-nitrophenyl)-2-propen-1-ones. Depending on the reduction method and on the presence of electron donating substituents on the A ring of 2-nitrochalcones one can modulate the formation of 2-arylquinolines, their N-oxides, and of 2-aminochalcones. The reduction of 3-hydroxy-1-(2-hydroxyphenyl)-3-(2-nitrophenyl)-2-propen-1-ones with stannous chloride in hydrochloric acid gave 2 '-aminoflavones and with ammonium formate and Pd/C yielded 2-(2-hydroxyaryl)-4-hydroxyquinolines.
Efficient Synthesis of Nitroflavones by Cyclodehydrogenation of 2′-Hydroxychalcones and by the Baker-Venkataraman Method
作者:Ana I. R. N. A. Barros、Artur M. S. Silva
DOI:10.1007/s00706-006-0550-9
日期:2006.12
Several nitroflavone derivatives were synthesized by cyclodehydrogenation of 2'-hydroxychalcones and by the Baker-Venkataraman approach, starting from 2'-hydroxyacetophenones and benzoic acid derivatives. Nitroflavones synthesised by the first synthetic approach were obtained in better global yields than those obtained by the later method. The structures of all new compounds were elucidated by microanalyses, 1D and 2D NMR, IR, and mass spectroscopic measurements.