13513-82-1Relevant articles and documents
Transfer hydrogenation of ketones catalyzed by 1-alkylbenzimidazole ruthenium(II) complexes
Oezdemir, Ismail,Sahin, Neslihan,Cetinkaya, Bekir
, p. 205 - 209 (2007)
Six [RuCl2(1-alkylbenzimidazole)(p-cymene)] complexes have been prepared and the new compounds characterized by C, H, N analyses, 1H NMR, and 13C NMR. The reduction of ketones to alcohols via transfer hydrogenation was ach
New dipyridylamine ruthenium complexes for transfer hydrogenation of aryl ketones in water
Romain, Charles,Gaillard, Sylvain,Elmkaddem, Mohammed K.,Toupet, Loic,Fischmeister, Cedric,Thomas, Christophe M.,Renaud, Jean-Luc
, p. 1992 - 1995 (2010)
A new family of cationic organometallic chloro compounds of the type [(arene)Ru(N,N)(Cl)]+ containing N,N-chelating dipyridylamine ligands has been synthesized and isolated as the chloride salts, which are water soluble and stable to hydrolysis. The resulting mononuclear ruthenium complexes catalyze the transfer hydrogenation of aryl ketones in aqueous solution to give the corresponding alcohols with good conversion and interesting recyclability.
Ruthenium complexes of triazole-based scorpionate ligands transfer hydrogen to substrates under base-free conditions
Kumar, Mukesh,Depasquale, Joseph,White, Nicholas J.,Zeller, Matthias,Papish, Elizabeth T.
, p. 2135 - 2144 (2013)
The first ruthenium complexes of bulky tris(triazolyl)borate (Ttz) ligands were synthesized, fully characterized, and studied as transfer hydrogenation catalysts. The structures of the complexes were (η6-arene)RuCl(N, N), where in each case N,N is a κ2-Ttz or bis(triazolyl)borate (Btz) ligand (arene = p-cymene (1, 3, 5, 6), benzene (2), C6Me 6 (4); N,N = TtzPh,Me* (1, 2), TtzMe,Me (3, 4), Ttz (5), Btz (6)). All but 5 were crystallographically characterized, and notably for 1 and 2 a rearranged ligand structure is observed (as indicated by an asterisk). These complexes were all effective catalysts for transfer hydrogenation of aryl ketones in isopropyl alcohol with base co-catalyst, with rates that were accelerated by moisture-free conditions. Complexes 1 and 2 are also effective catalysts for base-free transfer hydrogenation, and with 1 hydrogenation of several base-sensitive substrates was demonstrated. The ability of 1 to serve as a hydrogenation catalyst without base is attributed primarily to steric bulk, and a preliminary mechanism for formation of that active catalyst is proposed.
Fe-Catalyzed Anaerobic Mukaiyama-Type Hydration of Alkenes using Nitroarenes
Bhunia, Anup,Bergander, Klaus,Daniliuc, Constantin Gabriel,Studer, Armido
supporting information, p. 8313 - 8320 (2021/03/08)
Hydration of alkenes using first row transition metals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama-type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe-catalyzed anaerobic Markovnikov-selective hydration of alkenes using nitroarenes as oxygenation reagents is reported. The nitro moiety is not well explored in radical chemistry and nitroarenes are known to suppress free radical processes. Our findings show the potential of cheap nitroarenes as oxygen donors in radical transformations. Secondary and tertiary alcohols were prepared with excellent Markovnikov-selectivity. The method features large functional group tolerance and is also applicable for late-stage chemical functionalization. The anaerobic protocol outperforms existing hydration methodology in terms of reaction efficiency and selectivity.
Rhodium-Catalyzed Regiodivergent Synthesis of Alkylboronates via Deoxygenative Hydroboration of Aryl Ketones: Mechanism and Origin of Selectivities
Zhang, Bing,Xu, Xin,Tao, Lei,Lin, Zhenyang,Zhao, Wanxiang
, p. 9495 - 9505 (2021/08/04)
Here, we report an efficient rhodium-catalyzed deoxygenative borylation of ketones to synthesize alkylboronates, in which the regioselectivity can be switched by the choice of the ligand. The linear alkylboronates were obtained exclusively in the presence of P(nBu)3, and PPh2Me favored the formation of branched alkylboronates. The protocol also allows access to 1,1,2-triboronates from the readily available ketones. Mechanistic studies suggest that this Rh-catalyzed deoxygenative borylation of ketones goes through an alkene intermediate, which undergoes regiodivergent hydroboration to afford linear and branched alkylboronates. The different steric effects of PPh2Me and P(nBu)3 were found to be responsible for product selectivity by density functional theory calculations. The alkene intermediate can alternatively undergo sequential dehydrogenative borylation and hydroboration to deliver the triboronates.