Thioether ligands

Scheme 1.33 Test reaction with (+ )-camphor-derived pyridine thioether ligand.

Scheme 1.40 Test reaction with pyrrolidine thioether ligands.

A new class of easily accessible 1,2-disubstituted phosphinamidite-thioether ligands derived from Ugi s amine and based on a ferrocene motif has been... 

Cu-catalysed 1,4-additions of ZnEt2 to enones and nitroalkenes with BINOL-based thioether ligands. 

Cu-catalysed additions of ZnEt2 to Baylis-Hillman-derived allylic electrophiles with BINOL-based thioether ligand. 

Scheme 2.13 Cu-catalysed 1,4-addition of AlMcj to 4,4-disubstituted cyclohexa-2,5-dienone with thioether ligands.

Scheme 2.35 Zn-catalysed 1,4-addition of /-PrMgCI to cyclohexenone with crown thioether ligands.

In 2008, the titanium complex of a novel BINOL-based thiazole thioether ligand was found by Li et al. to be an efficient catalyst in the enantioselective... 

BINOL-based thiazole thioether ligand for additions of ZnEt2 to... 

In general, of the mixed phosphorus-thioether ligands that have been used in the asymmetric hydrogenation of prochiral olefins, the thioether-phosphinite ligands have provided some of the best results. As an example, a new class of thioether-phosphinite ligands developed by Evans et al. has recently proved to be very efficient for the rhodium-catalysed asymmetric hydrogenation of a... 

In addition, Peruzzini et al. developed, in 2007, iridium complexes of planar-chiral ferrocenyl phosphine-thioether ligands that were tested in the hydrogenation of simple alkyl aryl ketones.These complexes were diastereoselec-tively generated in high yields (85-90%) by addition of the corresponding... 

Scheme 8.33 Hydrogenations of alkyl aryl ketones with ferrocenyl phosphine-thioether ligands.

Henry reactions 317-20 hydrosilylations 333 organozinc reagents, addition to ketones 156-80 PrMgCl to cyclohexenone with crown thioether ligands 100-1 see also specific ZnEt2 and ZnR2 addition reactions... 

Oxygenation of the Ni1 complex (39) leads to 02 activation and 0-0 bond rupture with formation of a deep purple bis(/i-oxo)nickel(III) complex (40) supported by thioether ligands.184 Its electronic structure has been investigated by spectroscopic and DFT methods.185... 

Monodentate thioether ligands are relatively poor ligands towards Ni11. However, several Ni11 complexes with polydentate thioether ligands are known, where the coordination capability is enhanced by chelation. In particular, complexes with macrocyclic thioether ligands, which are discussed in Sections 6.3.4.10.l(iii) and 6.3.4.10.3, are very stable. 

Optically active amine-thioether ligands (492) have been investigated in nickel-catalyzed asymmetric cross-coupling reactions of Grigard reagents.1338... 

Coordination studies of acyclic thioether ligands to silver(I) centers has also been studied. Poly(alkylthio)aromatic systems have been used to form supramolecular silver(I) compounds. With the ligand 2,3,5,6-tetrakis(isopropylthio)benzoquinone the compound has a linear chain structure in which silver(I) has a tetrahedral coordination.1156 A similar structure has the compound with the hexakis(methylthio)benzene,1157 but with the hexakis(tolylthio)benzene the silver... 

Thioether ligand complexes are not very common, however, studies since the mid 1990s have dramatically increased the number of structurally characterized examples. Almost all of these compounds are with chelate or macrocyclic ligands that will stabilize thioether coordination. Mixed donor multidentate ligands containing thioether donors will be discussed in Section 6.8.11. 

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