Microwave-assisted solvent-free synthesis of a quinoline-3,4-dicarboximide library on inorganic solid supports

Inorganic solid supports are useful media for the rapid and efficient synthesis of a library of quinoline-3,4-dicarboximides. In particular, wet clay K10 was shown to be the best medium for the condensation reaction between 2-methylquinoline3,4-dicarboxylic anhydride and several primary amines. Microwave irradiation is essential for a rapid and complete conversion

Solid-supported nitrile oxides as stable and valuable reactive intermediates

1,3-Dipolar cycloadditions of Wang resin supported nitrile oxides have been performed with several dipolarophiles to afford 5-membered heterocycles in fair yields. The nitrile oxides displayed increased stability on the solid phase, allowing clean transformations into nitrosocarbonyl intermediates, which could be trapped with suitable dienes to afford hetero Diels-Alder cycloadducts in moderate yields

Chiral amplification in Diels-Alder and 1,3-dipolar cycloadditions catalyzed by bis(oxazoline)-Zn(II)-based chiral complexes

A Zn(II)-bis(oxazoline) chiral complex catalyzes the cycloaddition reactions of alkenoyl-oxazolidinones with both cyclopentadiene and diphenyl nitrone. The 1,3-dipolar cycloaddition becomes exo selective with an ee of up to 86%. While the Mg(II)-based catalysts give a linear relationship between the ligand's optical purity and the ee of the reaction product, a remarkable positive nonlinear effect was observed in both cycloadditions by using Zn(II) as the cationic core of the catalyst. The result may be rationalized by the formation of a stable, insoluble, and catalytically inactive heterochiral complex