171509-69-6Relevant articles and documents
Synthesis and Characterization of Gold(III) Adducts and Cyclometallated Derivatives with 2-Substituted Pyridines. Crystal Structure of Cl2>
Cinellu, Maria Agostina,Zucca, Antonio,Stoccoro, Sergio,Minghetti, Giovanni,Manassero, Mario,Sansoni, Mirella
, p. 2865 - 2872 (1995)
The 2-benzylpyridines HL reacted with AuCl3*2H2O or Na to give adducts or cyclometallated derivatives .The metallation reaction involves direct activation of a C-H bond of the phenyl substituent.With the 2-alkylpyridines NC5H4(CMe3)-2 and NC5H4(CH2CMe3)-2 (HL) only the tetrachloroaurate(III) salts were isolated.The structure of Cl2> has been determined by X-ray diffraction.It reveals a six-membered ring having a boat-like conformation: there is a rather short interaction between one hydrogen of the Me group in axial position and the gold atom, Au...H 2.56(5) Angstroem.The cyclometallated species react with PPh3 to give cationic complexes (1+) and with 1,2-bis(diphenylphosphino)ethane (dppe) to yield (1+).Under pressure (50 atm, 60 deg C) of CO extrusion of the metal occurs.The organic products formed likely arise from insertion of CO into the Au-C bond.The reactivity of the cycloaurated species is compared with that of analogous palladium(II) derivatives previously.
Cyclometallated gold(III) complexes as effective catalysts for synthesis of propargylic amines, chiral allenes and isoxazoles
Kung, Karen Ka-Yan,Lo, Vanessa Kar-Yan,Ko, Hok-Ming,Li, Gai-Li,Chan, Pui-Ying,Leung, King-Chi,Zhou, Zhongyuan,Wang, Ming-Zhong,Che, Chi-Ming,Wong, Man-Kin
supporting information, p. 2055 - 2070 (2013/08/23)
A series of cyclometallated gold(III) complexes [Au(CN)Cl2] 1a-l (HCN=arylpyridines) and a PEG-linked complex 1m were synthesized. Complexes 1a-m are effective in catalyzing the synthesis of propargylic amines, chiral allenes and isoxazoles. Six-membered ring cyclometallated gold(III) complexes 1f-l exhibited higher catalytic activity than five-membered ring cyclometallated gold(III) complexes 1a-e. The diastereoselectivity of propargylic amines could be tuned by using chiral aldehyde and/or amine substrates. Excellent enantioselectivities (90-98% ee) were achieved in chiral allene synthesis. Chiral allene racemization could be minimized by using 1f as catalyst. The PEG-linked catalyst 1m is the most catalytically active towards synthesis of propargylic amines, in which case a product turnover of 900 was achieved. Moreover, 1m could be repeatedly used for 12 reaction cycles, leading to an overall turnover number of 872. Copyright
