Norbomene catalysts, palladium complexes

Other Pd Derivatives and Related Reactions. Other chiral palladium complexes, such as (DIOP)2Pd° or (DIOP)(alkene)Pd°, can be prepared from (DIOP)PdCl2. These catalysts have afforded low levels of asymmetric induction (10% ee) in the hydro-cyanation of norbomene derivatives. ... 

Selective aromatic functionalization has been a permanent object of research since the ninenteenth century. Catalysis has offered a powerful tool to achieve this goal. Over the years we have worked out a complex catalytic system consisting of an inorganic compound such as a palladium salt and an organic molecule containing a strained double bond such as norbomene (1,2). We have seen that these two catalysts cooperatively react with an aromatic iodide, an alkyl iodide and a terminal olefin. The following equation reports an example (L = solvent and/or olefin) (3). 

To examine the differences in reactivity of various immobilized palladium pincer catalysts, small molecule, polymer-supported (poly(norbomene) - soluble, and Merrifield resin - insoluble), and silica-supported (SBA-15) pincer complexes were synthesized (Fig. 20.9) [44 6]. Both sulfur-containing (SCS) and phosphorous-containing (PCP) ligands were studied. 

Norbomene polymerization is the most versatile of the cycloolefin addition polymerizations. Single-site catalysts such as metallocene compounds, constrained geometry catalysts (CGCs), and nickel or palladium diimine complexes, used in combination with MAO or borate cocatalysts, are active for the copolymerization of norbomene with ethene. The stmctme of the norbomene homo- and copolymers can be widely influenced by the symmetry and stmcture of the ligands on the transition metal complexes. 

Figure 9 Multicomponent catalysts for norbomene polymerization based on cationic palladium-phosphine complexes (X=CI, NO2, O2CCF3 R=Ph, n-Bu, f-Bu, CeFs).

Single-site catalysts, such as metallocene compounds, CGCs, and nickel or palladium diimine complexes, used in combination with MAO or borate cocatalysts, are active for the copolymerization of norbomene with ethene. 

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