Gold complexes reactions

The gold complex, generated in situ from bis(4-isocyanocyclohexyl)gold(I) tetrafluoroborate and (A)-A-methyl-,V-[2-(dialkylamino)ethyl]-l-[(5)-r,2-bis(diphenylphosphino)ferrocenyl]eth-ylamine, is an effective catalyst for the aldol reaction of various aldehydes with methyl iso-cyanoacetate to give the trans- and cw-4,5-dihydro-l,3-oxazoles. Depending on the aldehyde, the transjeis product ratio ranges from 84 16 to 100 0, and the ee of the main diastereomer is between 72 and 97%26. 

The oxidation-reduction reactions of gold complexes. V. P. Dyadchenko, Russ. Chem. Rev. (Engl. Transl), 1982, 51,265-271 (66). 

A related dinuclear species 77, recently described, constitutes the first dinuclear gold(I) complex with heterobridged phosphor-1,1 -dithiolato moieties and bis(ylide) bridging ligands [ 102]. It is obtained by reaction between [ AuS2PPh2] and the diylide gold complex 74 (R=Me). No intermolecular Au-Au interaction is observed in 77 but the oxidative addition of chlorine to the product leads to a new complex 78 in which a single bond is formed between the two Au(II) centers (Scheme 26). 

Bardaji, M., Laguna, A., Perez, M.R. and Jones, P.G. (2002) Unexpected ring-opening reaction to a new cyanamide-fhiolate ligand stabilized as a dinuclear gold complex. Organometallics, 21, 1877. 

In addition to the simple reaction of a poly dentate ligand with [Au(C6F5)(tht)] the other versatile synthesis of di- and trinudear derivatives is the use of gold complexes as ligands. 

Polynuclear Au(I) pentafluorophenyl complexes can also be obtained by reaction of [AulCfiFsjItht)] with polydentate ligands or with gold complexes that still have different coordination sites or can be created before the subsequent reaction. The ligands or complexes that react with [Au(C6F5)(tht)] and the complexes obtained are listed in Table 3.6. 

Kitadai, K., Takahashi, M., Takeda, M., Bhargava, S.K., Priver, S.Fl. and Bennett, M.A. (2006) Synthesis, structures and reactions of cyclometalated gold complexes containing (2-diphenylarsino-n-methyl)phenyl (n = 5, 6). Dalton Transactions, (21), 2560—2571. 

Photoinduced Electron Transfer Reactions of Gold Complexes 273... 

Stability of the bidentate and multidentate complexes in aqueous solution [16] compared with monodentate complexes. Kinetic studies of gold(III) reactions with ethylenediamine and related ligands show that the initial displacement of one end of the chelate is most often followed by rapid reclosure of the ring, rather than displacement of the second bond to the metal ion [15]. 

Medicinally Important Gold Complexes, Their Analogs and Reactions 291... 

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