Succinates

Abstract: We present a theoretical study of the basic interactions occurring at supported hetereogenous Ziegler−Natta catalytic systems. We first investigated the interaction between prototypes of each class of industrially relevant internal donors (1,3-diethers, alkoxysilanes, phthalates, succinates) and the MgCl2 support. Our analysis indicates that donors can be separated into two classes. 1,3-Diethers and alkoxysilanes belong to the former because they have a short spacer between the coordinating O atoms and coordinate preferentially to the same Mg atom of the (110) lateral cut. Conversely, phthalates and succinates belong to the latter class because they have a longer spacer between the coordinating O atoms and thus can adopt a variety of coordination modes. Indeed, they can coordinate to both the (100) and (110) lateral cuts. In the last part of this manuscript we report on the stereo- and regioselective behavior of possible active Ti species with and without two succinate molecules coordinated in the proximi...