pot by subsequent ring-opening, reductions, and intra- and intermolecular Friedel–Crafts reactions, also in HFIP. Finally, owing to the high pharmacological relevance of the isochroman motif, the synthesis of drug analogues was demonstrated.
Synthesis of tetrahydroisoquinolines and isochromans via Pictet–Spengler reactions catalyzed by Brønsted acid–surfactant-combined catalyst in aqueous media
Perfluorooctanesulfonic acid (PFOSA), Bronsted acid-surfactant-combined catalyst, efficiently catalyzes the Pictet-Spengler reactions of beta-arylethyl carbamate derivatives with aldehydes in water. The present reaction is accelerated by the addition of 1, 1, 1,3,3,3-hexafluoro-2-propanol (HFIP). PFOSA in HFIP-water (10 v/v%) is also successfully applied to the oxa-Pictet-Spengler reactions of beta-arylethyl alcohol compounds. (C) 2007 Elsevier Ltd. All rights reserved.
Synthesis of isochromans via Fe(OTf)2-catalyzed Oxa-Pictet–Spengler cyclization
作者:Jimei Zhou、Chao Wang、Dong Xue、Weijun Tang、Jianliang Xiao、Chaoqun Li
DOI:10.1016/j.tet.2018.10.028
日期:2018.12
Fe(OTf)2 has been found to be an efficient catalyst for the Oxa-Pictet–Spengler cyclization reaction leading to isochromans. A series of substituted isochromans were obtained with good to excellent isolated yields by coupling β-arylethanols with aldehydes or ketals under the catalysis of 1 mol% of Fe(OTf)2 at 70 °C. Using a cheap, less-toxic catalyst with water as the only byproduct, this iron-catalyzed