Imidazolylidenes, oxazoline-imidazolylidene

The most selective catalyst in this series, complex 32 c, with very bulky substituents at the oxazoline and the imidazolylidene moiety, was used to hydrogenate a range of trisubstituted alkenes with enantiomeric excesses of greater than... 

Scheme 43 Synthesis of an iridium(I) complex bearing Burgess s chiral oxazoline-imidazolylidene ligand...

Bidentate oxazoline-imidazolylidene ligands, in which both units are linked by a chiral paracyclophane, have been studied in Bolm s group [129]. In this case, the planar chirality of the pseudo-orfho-paracyclophane is combined with the central chirality of an oxazoline (Scheme 48). Compounds 70 were tested in the asymmetric hydrogenation of olefins displaying moderate selectivity (ee s of up to 46% for dimethylitaconate in the presence of 70b). 

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