Reactions of guaiazulene with methyl terephthalaldehydate and 2-hydroxy- and 4-hydroxybenzaldehydes in methanol in the presence of hexafluorophosphoric acid: comparative studies on molecular structures and spectroscopic, chemical and electrochemical prope

Reactions of guaiazulene (1) with methyl terephthalaldehydate (2) and 2-hydroxy- and 4-hydroxybenzaldehydes (3 and 4) in methanol in the presence of hexafluorophosphoric acid at 25 °C for 2 h under aerobic conditions give the corresponding monocarbocation compounds 5-7 in 94, 89 and 97% yields, respectively. The title studies are reported.