Palladium complexes acetate-bipyridine

Helquist et al. [129] have reported molecular mechanics calculations to predict the suitability of a number of chiral-substituted phenanthrolines and their corresponding palladium-complexes for use in asymmetric nucleophilic substitutions of allylic acetates. Good correlation was obtained with experimental results, the highest levels of asymmetric induction being predicted and obtained with a readily available 2-(2-bornyl)-phenanthroline ligand (90 in Scheme 50). Kocovsky et al. [130] prepared a series of chiral bipyridines, also derived from monoterpene (namely pinocarvone or myrtenal). They synthesized and characterized corresponding Mo complexes, which were found to be moderately enantioselective in allylic substitution (up to 22%). 

It is remarkable that the palladium(O) complexes are inactive in the absence of chloroform.236 Palladium acetate-bipyridine complex has been reported to catalyse conjugate addition of arylboronic acids to a -unsaturated carbonyl compounds in aqueous media with high yields.237... 

Acetoxylation of arenes. Arenes are acetoxylated by acetic acid (sodium acetate can be added) with potassium persulfate as oxidant and palladium(II) acetate as catalyst. The reaction is unusual in that wie/a-acetoxylation predominates this selectivity can be enhanced by addition of a complexing amine such as 2,2 -bipyridine. Side-chain acetoxylation can be effected with some arenes. Thus mesitylene and durene arc acetoxylated mainly in the a-position of the substituents. ... 

Synthesis of neutral Ji-allylpalladium complexes having bisnitrogen ligands (mainly, those related to 2-(pyrazol-3-yl)pyridine, 2-(imidazol-2-yl)pyridine, and 2,2-bipyridine) and palladium-catalyzed cyclopropanation of ketene silyl acetals with allylic acetates 00YGK736. 

Oxidative addition of aryl halides to [Pd(dba)2] in the presence of tetramethylethylenediamine or 2,2 -bipyridine to produce cis- [Pd(N-N)(Ph)X] proceeds easily when iodides are used but with more difficulty with bromides. Methyllithium reacts with the iodo complexes to give the mixed dialkyls. Cross coupling of alkenylboronic and arylboronic acids with alkenes is catalysed by palladium acetate in acetic acid. The reaction is believed to occur by oxidative addition of the carbon-boron bond across an in situ Pd(0) centre. 35... 

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