Facile and efficient chemical functionalization of aliphatic polyesters by cross metathesis

An effective preparation of new tailor-made macromolecular materials via a combination of two (atom-efficient) catalytic transformations is reported. First, new aliphatic polyesters with alternated composition have been prepared using a salen aluminum catalyst system. Next, the pendant vinyl moieties in those copolymers have been selectively transformed into various functional groups by metathesis in the presence of homogeneous Grubbs catalysts. The latter metathesis reaction has been optimized in terms of catalytic activity and selectivity, to define the conditions for an effective and safe procedure that does not affect the macromolecular architecture. All polymer materials have been analyzed by H-1, and C-13 NMR spectroscopy, to diagnose the catalyst selectivities in the copolymerization and metathesis processes.