366801-25-4Relevant academic research and scientific papers
Novel heteroannulation through copper catalysis: A highly regio- and stereoselective synthesis of 2-substituted 3,1-benzoxathiinones
Kundu,Nandi
, p. 415 - 417 (2007/10/03)
A highly regio- and stereoselective method, comprising a cuprous iodide-catalysed cyclisation as a key step, gives an easy access to (E)-2-(2-arylvinyl)-3,1-benzoxathiin-4-ones 16-22.
A general and highly regio and stereoselective method for the synthesis of (E)-2-(2-arylvinyl)-3,1-benzoxathiin-4-ones through palladium-copper catalysis
Nandi, Bidisha,Kundu, Nitya G.
, p. 1649 - 1655 (2007/10/03)
A palladium-copper-catalysed procedure for the synthesis of (E)-2-(2-arylvinyl)-3,1-benzoxathiin-4-ones 5a-5h is developed. 3-[2-(Methoxycarbonyl)phenylthio]propyne 2 reacts with aryl iodides 3a-3h in the presence of bis(triphenylphosphine)palladium(II) dichloride, copper(I) iodide and triethylamine in acetonitrile to furnish the disubstituted alkynes 4a-4h in good yields (70-84%). These on alkaline hydrolysis and subsequent cyclisation of the carboxylic acids formed with copper(I) iodide (20 mol%) and triethylamine in tetrahydrofuran under reflux afford (E)-2-(2-arylvinyl)-3,1-benzoxathiin-4-ones 5a-5h in 61-70% yield rather than the expected benzoxathiepinones 6. The reactions of (E)-2-(2-arylvinyl)-3,1-benzoxathiin-4-ones 5a and 5g with nucleophites and the hydrogenation of compounds 5a, 5b and 5d are also studied.
