Nanosilica sulfuric acid is found to be a new, powerful and reusable heterogeneous catalyst for the rapid synthesis of 3-hydroxyphthalans via condensation of aromatic aldehydes and 3-hydroxybenzyl alcohols under conventional heating and microwave irradiation. Scale-up preparation of these heterocycles is also carried out. (C) 2011 Published by Elsevier Ltd.
The Oxa-Pictet–Spengler Reaction: A Highlight on the Different Efficiency between Isochroman and Phthalan or Homoisochroman Derivative Syntheses
conditions and with very good yield by a one-pot synthesis based on a modified oxa-Pictet–Spenglerreaction. In this paper, we demonstrate that the above reaction is also useful for the synthesis of hydroxyphthalans, and we discuss the effects of the substituents on the alcoholic aromatic ring on the course of the reaction, as well as those on the aldehydic structure. We also report a synthesis of h