F. Hollwedel et G. Kossmehl, Novell isochroman-3-ones for the curing of unsaturated polyesters via Diels-Alder reaction, MACRO CH P, 200(12), 1999, pp. 2612-2622
The synthesis of some new 4-hydroxy, 4-butyloxy, 4-propionyloxy, and 4-acry
loyloxy substituted isochroman-3-ones is described. The influence of the su
bstitution pattern in position I and 4 on the CO2 elimination, which leads
to high reactive ortho-quinodimethanes, is investigated. The saturated comp
ounds are used for model reactions with diethyl maleate to study the Diels-
Alder reaction and to explain the curing mechanism of unsaturated polyester
s. The acrylic ester is copolymerized with styrene to give a reactive copol
ymer which can easily cure unsaturated polyesters at 170 degrees C in two m
ins without toxic byproducts.