A new protocol for the synthesis of various 1,2,3,4-tetrasubstituted 1,4-dihydropyridines from enamino or carbonylic derivatives promoted by Mg(ClO4)2 is presented.
Zn(ClO 4 ) 2 .6H 2 O proved to be a very powerfulcatalyst for the condensation of primary and secondary amines with β-ketoesters to give N-substituted β-enaminoesters.
Metal- and Solvent-Free Synthesis of m-Terphenyls by an Iodine-Catalyzed Tandem Formal [3+3]-Cycloaddition/Oxidation
作者:C. Uma Maheswari、Thangavel Pavithra、Gnanaoli Karthiyayini、Subbiah Nagarajan、Vellaisamy Sridharan
DOI:10.1055/a-1903-5174
日期:——
A tandem formal [3+3]-cycloaddition/oxidation between chalcones and β-enamine esters, employing iodine as a catalyst, was developed for the construction of various substituted m-terphenyls. A wide range of chalcones and β-enamine esters were tested under metal- and solvent-free conditions for the synthesis of substituted m-terphenyls in good to excellent yields in the presence of sulfur as an oxidant