606-46-2Relevant articles and documents
C(sp3)-F bond activation of CF3-substituted anilines with catalytically generated silicon cations: Spectroscopic evidence for a hydride-bridged Ru-S dimer in the catalytic cycle
Stahl, Timo,Klare, Hendrik F. T.,Oestreich, Martin
, p. 1248 - 1251 (2013/03/29)
Heterolytic splitting of the Si-H bond mediated by a Ru-S bond forms a sulfur-stabilized silicon cation that is sufficiently electrophilic to abstract fluoride from CF3 groups attached to selected anilines. The ability of the Ru-H complex, generated in the cooperative activation step, to intramolecularly transfer its hydride to the intermediate carbenium ion (stabilized in the form of a cationic thioether complex) is markedly dependent on the electronic nature of its phosphine ligand. An electron-deficient phosphine thwarts the reduction step but, based on the Ru-S catalyst, half of an equivalent of an added alkoxide not only facilitates but also accelerates the catalysis. The intriguing effect is rationalized by the formation of a hydride-bridged Ru-S dimer that was detected by 1H NMR spectroscopy. A refined catalytic cycle is proposed.
Homogeneous catalytic hydrogenation of amides to amines
Coetzee, Jacorien,Dodds, Deborah L.,Klankermayer, Jürgen,Brosinski, Sandra,Leitner, Walter,Slawin, Alexandra M. Z.,Cole-Hamilton, David J.
supporting information, p. 11039 - 11050 (2013/09/02)
Hydrogenation of amides in the presence of [Ru(acac)3] (acacH=2,4-pentanedione), triphos [1,1,1-tris- (diphenylphosphinomethyl)ethane] and methanesulfonic acid (MSA) produces secondary and tertiary amines with selectivities as high as 93 % provided that there is at least one aromatic ring on N. The system is also active for the synthesis of primary amines. In an attempt to probe the role of MSA and the mechanism of the reaction, a range of methanesulfonato complexes has been prepared from prepared from [Ru(acac) 3], triphos and MSA, or from reactions of [RuX-(OAc)(triphos)] (X=H or OAc) or [RuH2(CO)(triphos)] with MSA. Crys-tallographically characterised complexes include: [Ru(OAc-κ1O) 2(H2O)-(triphos)], [Ru(OAc-κ2O,O') (CH3SO3-κ1O)(triphos)], [Ru(CH 3SO3-κ1O)2-(H 2O)(triphos)] and [Ru2(μ-CH3SO 3)3-(triphos)2][CH3SO3], whereas other complexes, such as [Ru(OAc-κ1O)(OAc- κ2O,O')(triphos)],[Ru(CH3SO3- κ1O)(CH3SO3-κ2O,O')- (triphos)], H[Ru(CH3SO3-κ1O) 3-(triphos)], [RuH(CH3SO3-κ1O) (CO)-(triphos)] and [RuH(CH3SO3-k2O,O')- (triphos)] have been characterised spectroscopically. The interactions between these various complexes and their relevance to the catalytic reactions are discussed.
Cu(ii)-catalyzed C-H (SP3) oxidation and C-N cleavage: Base-switched methylenation and formylation using tetramethylethylenediamine as a carbon source
Zhang, Lei,Peng, Chen,Zhao, Dan,Wang, Yue,Fu, Hai-Jian,Shen, Qi,Li, Jian-Xin
supporting information; experimental part, p. 5928 - 5930 (2012/07/27)
Base-switched methylenation and formylation using tetramethylethylenediamine (TMEDA) as a carbon source have been achieved under mild conditions, catalyzed by CuCl2, with atmospheric oxygen as oxidant. Bisindolylmethanes, diphenylmethanes and 3-formylindoles were synthesized with excellent regioselectivity and good yield.
