Polyethylenimines PEIs with Adducts that Self-assemble into Catalytic Moieties

Polyethylenimines (PEIs) with Adducts that Self-assemble into Catalytic Moieties 

As rationally designed multinuclear catalysts for transesterification of HPNPP, metal complexes such as 5 have been designed [42]. By random attachment of lauryl groups and Ni(n) complexes of terpyridine (TP) to PEI (6) we have synthesized a polymer that has much higher catalytic activity than 5 for the same reaction [43]. The contents of the pendant groups were varied in several combinations, and the best catalyst (]Ni(ii)TP]5Lau12PEI) contained 5 residue mol% Ni(n)TP and 12 residue mol% lauryl group. 

In water, the lauryl and terpyridyl residues are expected to form hydrophobic clusters (6) on the backbone of PEI. An active site consisting of two or more metal ions can form in the cluster. Its structure depends on the contents of lauryl and terpyridyl residues. An active site obtained by combinatorial attachment of the pendants catalyzed transesterification of HPNPP apparently by using adjacent metal centers (7). In this work, we created the active site by self-assembly of hydrophobic pendants attached to the backbone of PEI, taking advantage of the branched and flexible structure of the polymer. 

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