FI catalysts for olefin polymerization--a comprehensive treatment.

Metal catalysts for the vinyl/addition polymerization of norbornene

The opening up of new markets, particularly in the Far East, is expected to increase the industrial demand for more (and new) plastic materials. In turn, this will drive the need for further catalyst development, with increased efficiency and with the capacity to easily control the resulting polymer properties being high on the agenda. With this in mind, tailoring the pre-catalyst structure has proved to be a very successful strategy, and has allowed for the elucidation of a number of structure–activity trends. A particularly fruitful synthetic avenue has been the deployment of multi-dentate ancillary ligands bearing one or more substituents containing additional functionality, capable of weakly binding to the metal. Such a method is versatile and allows for the incorporation of a wide range of functionality. Furthermore, benefits of such an approach include the ability to control the % incorporation of co-monomers, in situ screening, low co-catalyst loadings (versus activity enhancement) as well as control over the resultant polymer structure. This review underlines the efforts made in the last few years with regard to the use of tridentate ligands and beyond in the field of α-olefin polymerization using catalytic systems based on group IV metals.

Tridentate ligands and beyond in group IV metal α-olefin homo-/co-polymerization catalysis

Well-defined vanadium complexes as the catalysts for olefin polymerization

The Michael reaction has been the subject of numerous reviews. Furthermore, the first review on anti-Michael addition has been published. The present review focuses only on the functionalization of indoles and the pyrroles via Michael additions because of the potential biological activity exhibited by these compounds.

Functionalization of Indole and Pyrrole Cores via Michael-Type Additions

The Ti complexes containing tridentate [O-NS R ] (R = Me, i Pr) ligands with alkylthio sidearms were prepared. The methylthio ether complex (R=Me shown in the Scheme) exhibits an excellent activity for copolymerization of ethylene with norbornene upon activation with MMAO, which is 10 times more active than the corresponding phenylthio one (R = Ph).

Ethylene‐Norbornene Copolymerization by New Titanium Complexes Bearing Tridentate Ligands. Sidearm Effects on Catalytic Activity

Tandem Michael additions of indole derivatives to 3-nitrocoumarins 2, followed by MVK, in one pot, has been developed for the synthesis of multi-functionalized 3,4-dihydrocoumarins bearing a quaternary stereocenter. The reaction proceeds with high diastereoselectivities in good to excellent yields.

Zhi Ma

Papers

Ethylene‐Norbornene Copolymerization by New Titanium Complexes Bearing Tridentate Ligands. Sidearm Effects on Catalytic Activity

Diastereoselective Tandem Michael Additions of Indoles to 3-Nitrocoumarin Derivatives and Methyl Vinyl Ketone