110-12-3Relevant articles and documents
6,6′-Dihydroxy terpyridine: A proton-responsive bifunctional ligand and its application in catalytic transfer hydrogenation of ketones
Moore, Cameron M.,Szymczak, Nathaniel K.
, p. 400 - 402 (2013)
The ligand 6,6′-dihydroxy terpyridine (dhtp) is presented as a bifunctional ligand capable of directing proton transfer events with metal-coordinated substrates. Solid-state analysis of a Ru(ii)-dhtp complex reveals directed hydrogen-bonding interactions of the hydroxyl groups of dhtp with a Ru-bound chloride ligand. The utility of dhtp was demonstrated by chemoselective transfer hydrogenation of ketones.
CONJUGATE ADDITIONS OF GRIGNARD REAGENTS TO α,β-UNSATURATED KETONES MEDIATED BY DIAMINE ZINC(II)MONOALKOXIDES
Jansen, Johan F. G. A.,Feringa, Ben L.
, p. 3593 - 3596 (1988)
A method for zinc mediated 1,4-additions of Grignard reagents with alkoxides as non-tranferable ligands is described.Using a chiral TMEDA analogue upto 14 percent enantiomeric excess was achieved.
Water soluble polymer-surfactant complexes-stabilized Pd(0) nanocatalysts: Characterization and structure-activity relationships in biphasic hydrogenation of alkenes and α,β-unsaturated ketones
Albuquerque, Brunno L.,Denicourt-Nowicki, Audrey,Mériadec, Cristelle,Domingos, Josiel B.,Roucoux, Alain
, p. 144 - 153 (2016)
A suitable approach to stabilize palladium nanoparticles in water as a green reaction medium for catalytic hydrogenation reactions is described. Supramolecular self-assemblies, obtained through the mixture of modified polyethyleneimines as amphiphilic polymers and water-soluble ammonium salts as surfactants, were used as efficient protective agents in the synthesis of Pd(0) nanospecies. The size and dispersion of the nanoparticles prepared with these original self-assemblies were characterized by TEM, SAXS and DLS techniques. The performances of the catalysts according to the polymer-surfactant mixtures were investigated in the hydrogenation of alkenes and α,β-unsaturated ketones in pure biphasic water/substrate medium, under mild conditions (room temperature and 1 bar H2). The nanocatalysts showed efficient catalytic activities and selectivity towards C=C bonds. From investigations, the polymer-surfactant complexes act as cooperative protective agents and a pertinent structure-activity relationship was proposed based on the zeta-potential values and the catalytic activity of the resulting colloids.
Simultaneous Preparation of (S)-2-Aminobutane and d -Alanine or d -Homoalanine via Biocatalytic Transamination at High Substrate Concentration
Li, Jianjiong,Wang, Yingang,Wu, Qiaqing,Yao, Peiyuan,Yu, Shanshan,Zhu, Dunming
supporting information, (2022/03/01)
(S)-2-Aminobutane, d-alanine, and d-homoalanine are important intermediates for the production of various active pharmaceutical ingredients and food additives. The preparation of these small chiral amine or amino acids with high water solubility still demands searching for efficient methods. In this work, we identified an ω-transaminase (ω-TA) from Sinirhodobacter hungdaonensis (ShdTA) that catalyzed the kinetic resolution of racemic 2-aminobutane at a concentration of 800 mM using pyruvate as the amino acceptor, leading to the simultaneous isolation of enantiopure (S)-2-aminobutane and d-alanine in 46% and 90% yield, respectively. In addition, (S)-2-aminobutane (98% ee) and d-homoalanine (99% ee) were isolated in 45% and 93% yield, respectively, in the kinetic resolution of racemic 2-aminobutane at a concentration of 400 mM coupled with deamination of l-threonine by threonine deaminase. We thus developed a biocatalytic process for the practical synthesis of these valuable small chiral amine and d-amino acids.
Methanol as hydrogen source: Chemoselective transfer hydrogenation of α,β-unsaturated ketones with a rhodacycle
Aboo, Ahmed H.,Begum, Robina,Zhao, Liangliang,Farooqi, Zahoor H.,Xiao, Jianliang
, p. 1795 - 1799 (2019/11/11)
Methanol is a safe, economic and easy-to-handle hydrogen source. It has rarely been used in transfer hydrogenation reactions, however. We herein report that a cyclometalated rhodium complex, rhodacycle, catalyzes highly chemoselective hydrogenation of α,β-unsaturated ketones with methanol as the hydrogen source. A wide variety of chalcones, styryl methyl ketones and vinyl methyl ketones, including sterically demanding ones, were reduced to the saturated ketones in refluxing methanol in a short reaction time, with no need for inter gas protection, and no reduction of the carbonyl moieties was observed. The catalysis described provides a practically easy and operationally safe method for the reduction of olefinic bonds in α,β-unsaturated ketone compounds.
Efficient Palladium(0) supported on reduced graphene oxide for selective oxidation of olefins using graphene oxide as a ‘solid weak acid’
Gao, Xi,Zhou, Jianhao,Peng, Xinhua
, p. 73 - 78 (2019/02/06)
Selective oxidation of olefin derivatives to ketones has made innovative development over palladium(0) supported on reduced graphene oxide. Compared to traditional Wacker oxidation, the novel method offers an economical and environment-friendly option by using graphene oxide (GO) as a ‘solid weak acid’ instead of classical homogeneous catalysts like H2SO4 and CF3COOH. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscopy images of Pd0/RGO showed that the nanoscaled Pd particles generated at the flake structure of reduced graphene oxide. Under optimized condition, up to 44 kinds of ketones with different structures can be prepared with excellent yields.
Iminyl Radical-Triggered Intermolecular Distal C(sp3)-H Heteroarylation via 1,5-Hydrogen-Atom Transfer (HAT) Cascade
Gu, Yu-Rui,Duan, Xin-Hua,Chen, Li,Ma, Zhi-Yong,Gao, Pin,Guo, Li-Na
supporting information, p. 917 - 920 (2019/02/14)
An efficient iron-catalyzed intermolecular remote C(sp3)-H heteroarylation of alkyl ketones has been developed via an iminyl radical-triggered 1,5-hydrogen-atom transfer (HAT) cascade. This protocol was amenable to a wide variety of alkyl ketones and heteroaryls, thus providing a straightforward method for the late-stage functionalization of alkylketones and heteroaryls.
Carbonylation of tertiary carbon radicals: synthesis of lactams
Yin, Zhiping,Zhang, Zhuan,Zhang, Youcan,Dixneuf, Pierre H.,Wu, Xiao-Feng
supporting information, p. 4655 - 4658 (2019/05/09)
Herein, we disclose an interesting iron-catalyzed approach for the carbonylation of a tertiary carbon radical. The tertiary carbon radical generated from a 1,5-hydrogen atom transfer can be captured by CO gas smoothly. Various six-membered lactams were constructed chemo-selectively in high yields.
Biocatalytic Racemization Employing TeSADH: Substrate Scope and Organic Solvent Compatibility for Dynamic Kinetic Resolution
Pop?oński, Jaros?aw,Reiter, Tamara,Kroutil, Wolfgang
, p. 763 - 768 (2018/02/27)
Racemization in combination with a kinetic resolution is the base for a dynamic kinetic resolution (DKR). Biocatalytic racemization was successfully performed for a broad scope of sec-alcohols by employing a single alcohol dehydrogenase (ADH) variant from Thermoanaerobacter pseudoethanolicus (formerly T. ethanolicus; TeSADH W110A I86A C295A). The catalyst employed as a lyophilized whole cell preparation or cell free extract, which tolerated various non-water miscible organic solvents under micro-aqueous or two-phase conditions, whereby cyclohexane and n-hexane suited best. Various concepts for combining the enzymatic racemization with an enzymatic kinetic resolution to achieve overall a bis-enzymatic DKR were evaluated. A proof of concept showed a successful DKR with racemization in aqueous phase combined with acylation in the organic phase.
Iminyl Radical-Mediated Controlled Hydroxyalkylation of Remote C(sp3)-H Bond via Tandem 1,5-HAT and Difunctionalization of Aryl Alkenes
Ma, Zhi-Yong,Guo, Li-Na,Gu, Yu-Rui,Chen, Li,Duan, Xin-Hua
supporting information, p. 4341 - 4347 (2018/10/20)
A visible-light mediated γ-hydroxyalkylation of ketones via C(sp3)-H functionalization has been developed under redox neutral conditions. This protocol relies on the iminyl radical-triggered 1,5-HAT followed by oxyalkylation of alkenes, wherein C?C and C?O bonds were constructed in one step. This three-component reaction features mild conditions, wide substrate scope and excellent functional group tolerance, thus providing a facile and highly efficient access to complex valuable ketones. (Figure presented.).
