936327-50-3Relevant academic research and scientific papers
Convenient one-pot protocol for an exclusive synthesis of 4-cyano/ethoxycarbonyl-2,2-dimethyl-2H-chromene and/or 3-cyano/ethoxycarbonyl-2- isopropyl-benzo[b]furan from a single oxo-ylide
Rao, V. V. V. N. S. Rama,Yadla,Rao, P. Shanthan
, p. 537 - 545 (2007)
[{2-(Fluoroaryloxy)-2-methyl-propanoyl}-(cyano/ethoxycarbonyl) methylene]triphenylphosphoranes underwent microwave-assisted tandem intramolecular Wittig and Claisen rearrangement and internal cyclization reactions to afford fluoro-substituted 2,2-dimethyl-2H-chromenes and/or 2-isopropyl-benzo[b]furans in good yield. Upon controlled microwave irradiation in the presence of Nafion H catalyst in xylene, the oxo-ylides selectively formed 4-cyano/ethoxycarbonyl-2,2-dimethyl-2H-chromenes. Microwave irradiation of the same oxo-ylide in the presence of K2CO3 as catalyst or in a polar solvent-like sulfolane resulted in the exclusive formation of the corresponding fluoro-substituted 3-cyano/ethoxycarbonyl-2-isopropyl-benzo[b]furans. Copyright Taylor & Francis Group, LLC.
