TY  - JOUR
ID  - pittir25723
UR  - http://d-scholarship-dev.library.pitt.edu/25723/
IS  - 15
A1  - Wipf, P
A1  - Xu, W
Y1  - 1995/04/10/
N2  - In situ prepared Cp2ZrCl? catalyzes the formation of dioxolenium ions from ?,?-unsaturated epoxy esters. As a consequence of this activation process, acrylate, methacrylate and crotonate derivatives undergo a rapid and stereoselective cationic [4+2] cycloaddition with a wide range of dienes. Ring-extended carboxylic acid derivatives are formed in 1-7 h at 0-21 °C and in 50-90% yield after saponification of the intermediate diol esters. Simple Lewis acid catalysis by Cp2ZrCl? can be excluded on the basis of the experimental results. © 1995.
JF  - Tetrahedron
VL  - 51
SN  - 0040-4020
TI  - Zirconocene-catalyzed cationic Diels-Alder reactions
SP  - 4551 
AV  - public
EP  -  4562
ER  -