78589-58-9Relevant academic research and scientific papers
NOUVEAU MODE DE CYCLYSATION DE CETO-YLURES. APPLICATION A UNE SYNTHESE IGINALE D'ACYL-3 HYDROXY-4-COUMARINES ET DE L'HYDROXY-11 BENZO-(b) 12 XANTHONE-12
Babin, P.,Dunogues, J.,Petraud, M.
, p. 1131 - 1139 (1981)
The thermal decomposition of keto-ylides resulting from the reaction of m- and p-acetoxy benzoyl chlorides with Ph3P=CH-COOMe leads, after saponification to m- and p-phenylpropiolic acid respectively.Ortho substitution by an acyl group generally changes the orientation of the reaction.Thus o-acetoxy-, benzoyloxy- or phenylacetoxy benzoyl chlorides respectively afford: and (R=Me,Ph) in satisfactory yields.Saponification of the first and second ones gives: (R=Me, Ph).This constitutes a new, convenient route to 3-acyl 4-hydroxy cumarins and 11-hydroxy 12H-benzoxanthene 12-one.Formation of these last products involves the carbonyl of the acyloxy-substituent and not of the acyl chloride as previously observed in these series.
