Inverse Electron Demand Diels-Alder Reactions of Heterodienes Catalyzed by Potassium Hydrogen Sulfate: Diastereoselective, One-Pot Synthesis of Pyranobenzopyrans, Furanobenzopyrans and Tetrahydroquinolines Derivatives
作者:Paramasivan T. Perumal、R. Senthil Kumar、Rajagopal Nagarajan
DOI:10.1055/s-2004-822332
日期:——
Potassiumhydrogensulfate catalyzes the one-pot three components coupling of aldehydes, anilines, and electron rich dienophiles such as dihydropyran, dihydrofuran, ethyl vinylether, and cyclopentadiene. With o-hydroxybenzaldehyde, the reaction probably proceeds through the formation of o-quinonemethide intermediate, which subsequently undergoes cycloaddition with cyclic and acyclic enol ethers leading
UREA NITRATE CATALYZED IMINO DIELS-ALDER REACTIONS: SYNTHESIS OF CYCLOPENTAQUINOLINES, PYRANOQUINOLINES, AND FUROQUINOLINE DERIVATIVES
作者:Marimuthu Anniyappan、Rajagopal Nagarajan、Paramasivan T. Perumal
DOI:10.1081/scc-120001514
日期:2002.1.1
ABSTRACT Urea nitrate is found to be an efficient catalyst for the imino Diels-Alder reaction of aldimines with cyclopentadiene, 3,4-dihydropyran and dihydrofuran is reported for the first time. One pot synthesis of cyclopentaquinolines from benzaldehyde, aromatic amines with cyclopentadiene catalyzed by urea nitrate is also reported.
Triphenyl phosphonium perchlorate—an efficient catalyst for the imino Diels–Alder reaction of imines with electron rich dienophiles. Synthesis of pyranoquinoline, furoquinoline and phenanthridine derivatives
作者:Rajagopal Nagarajan、Sundararajan Chitra、Paramasivan T Perumal
DOI:10.1016/s0040-4020(01)00185-5
日期:2001.4
Triphenyl phosphonium perchlorate (TPP) is found to be an efficient catalyst for the imino Diels-Alder reaction of aldimines with cyclopentadiene and 3,4-dihydro-2H-pyran is reported for the first time. One pot synthesis of furoquinoline, cyclopentaquinolines and phenanthridine catalysed by TPP is also reported in good yields. (C) 2001 Elsevier Science Ltd. All rights reserved.
Role reversal in the cyclocondensation of cyclopentadiene with heterodienophiles derived from aryl amines and aldehydes: Synthesis of novel tetrahydroquinolines