Tunable Synthesis of 3‑Acyl-2-naphthols and 3‑Substituted Isocoumarins via Jones Reagent Promoted Cascade Reactions of 2‑(4-Hydroxy-but-1-ynyl)benzaldehydes

Novel
and efficient synthesis of 3-acyl-2-naphthols and 3-substituted
isocoumarins via the tunable cascade reactions of 2-(4-hydroxy-but-1-ynyl)­benzaldehydes
have been developed. Treatment of 2-(4-hydroxy-but-1-ynyl)­benzaldehydes
with 0.7 equiv of Jones reagent in CH3CN and subsequent
purification through column chromatography on silica gel pre-eluted
with Et3N afforded 3-acyl-2-naphthols with high efficiency.
When the same substrates were treated with 3 equiv of Jones reagents
in acetone, on the other hand, 3-substituted isocoumarins could be
obtained in good yields.