Silica-supported polyphosphoric acid in the synthesis of 4-substituted tetrahydroisoquinoline derivatives

5-Aryloxazolidines as Reagents for Double Alkylation of Arenes: A Novel Synthesis of 4-Aryltetrahydroisoquinolines

5-Aryloxazolidines react with arenes under Lewis or Brønsted acid conditions via the Friedel-Crafts/Pictet-Spengler double alkylation sequence to give alkaloid-like 4-aryltetrahydroisoquinolines in 12-94% yields. Three approaches for the controlled insertion of substituents into the target molecules and application of oxazolidine derivatives such as 1-arylethanol-2-amines or 4-hydroxytetrahydroisoquinolines in the alkylation of arenes are also described. An unprecedented two-step easily scalable synthesis of the 4-aryltetrahydroisoquinoline core from aromatic aldehyde was achieved applying oxazolidine methodology.

A novel generation of hybrid photochromic vinylidene-naphthofuran silica nanoparticles through fine-tuning of surface chemistry

Hybrid vinylidene-naphthofuran nanosilicas with fast and reversible photochromism under UV/sunlight were fabricated through fine-tuning of surface chemistry and a grafting process.