80948-35-2Relevant academic research and scientific papers
Pyrylium Compounds. 31. Reaction of 3-Alkyl-2,4,6-triarylpyrylium Salts with 1,3-Diketonates: A Method for the Preparation of 3-Acylsubstituted Benzophenones
Zimmermann, Thomas,Fischer, Gerhard W.
, p. 359 - 372 (2007/10/02)
Reaction of 3-alkyl-2,4,6-triarylpyrylium salts with 1,3-diketones in the presence of one equivalent of triethylamine or potassium tert-butoxide does not lead - as originally suspected - to the primary adducts of 2H-pyran structure 6, but to the open-chain valence isomers 7.Treatment of the latter with one equivalent of tert-butoxide in tert-butyl alcohol gives the same 3-alkyl-2,4,6-triarylacetophenones 9 which are obtained directly from 5, 1,3-diketones and two equivalents of potassium tert-butoxide.However, on treating 7 with aqueous ethanolic sodium hydroxide 3-acylsubstituted benzophenones 10 are formed in good yields.The reaction sequence 5 --> 7 --> 10 can also be performed through a one-pot-procedure. - The i.r., u.v., n.m.r. and mass spectroscopic data of the novel products 7, 9, and 10 are reported.
