Polymer-supported benzotriazoles as catalysts in the synthesis of tetrahydroquinolines by condensation of aldehydes with aromatic amines.
Four polymer-supported benzotriazoles were prepared by linkage of 5-(hydroxymethyl)benzotriazole and benzotrizaole-5-carboxylic acid with Wang resin, Merrifield resin, and (monomethoxy)poly(ethylene glycol). The solid-phase and liquid-phase syntheses of tetrahydroquinolines were achieved by two-pair coupling reactions of aldehydes and aromatic amines using these polymer-supported benzotriazoles as the promoters. The ether-type benzotriazole prepared by loading 5-(hydroxymethyl)benzotriazole onto Merrifield resin turned out to be the catalyst of choice. Thus, a series of tetrahydroquinoline products were obtained in high purity by simple filtration, and the resin was recovered for reuse without loss of activity.
Talukdar
S
S
Department of Chemistry, National Taiwan University, Taipei, 106, Taiwan, Republic of China.
Chen
R J
RJ
Chen
C T
CT
Lo
L C
LC
Fang
J M
JM