Premium
Doubly Vinylogous 4 H ‐Pyrones from Pyrylium Salts and Aryl β‐Chlorovinyl Ketones
Author(s) -
Balaban Alexandru T.,
Fahmy Mahmoud,
Gheorghiu Mircea D.,
Wray Victor
Publication year - 1983
Publication title -
liebigs annalen der chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0170-2041
DOI - 10.1002/jlac.198319831013
Subject(s) - chemistry , tautomer , aryl , protonation , perchlorate , fragmentation (computing) , pyridine , medicinal chemistry , yield (engineering) , photochemistry , organic chemistry , ion , alkyl , materials science , computer science , metallurgy , operating system
Aryl β‐chlorovinyl ketones react with the methyl group of 2,6‐di‐ tert ‐butyl‐4‐methylpyrylium perchlorate in the presence of pyridine to yield doubly vinylogous 4 H ‐pyrones 3 . Only one configuration and conformation from the eight possible structures appears to be present according to IR, UV‐VIS, and NMR data. The mass spectral fragmentation is discussed. Protonation of 3 converts these products into pyrylium salts which may exist in three tautomeric forms. Their structure in solution and in the solid state is discussed.