70111-05-6Relevant articles and documents
Unmasking the Hidden Carbonyl Group Using Gold(I) Catalysts and Alcohol Dehydrogenases: Design of a Thermodynamically-Driven Cascade toward Optically Active Halohydrins
Escot, Lorena,González-Granda, Sergio,Gotor-Fernández, Vicente,Lavandera, Iván
, p. 2552 - 2560 (2022/02/16)
A concurrent cascade combining the use of a gold(I) N-heterocyclic carbene (NHC) and an alcohol dehydrogenase (ADH) is disclosed for the synthesis of highly valuable enantiopure halohydrins in an aqueous medium and under mild reaction conditions. The meth
Quinone Reduction by Organo-Osmium Half-Sandwich Transfer Hydrogenation Catalysts
Bolitho, Elizabeth M.,Coverdale, James P. C.,Sadler, Peter J.,Schünemann, Volker,Wolny, Juliusz A.,Worby, Nathan G.
, p. 3012 - 3023 (2021/09/13)
Organo-osmium(II) 16-electron complexes [OsII(η6-arene)(R-PhDPEN)] (where η6-arene =para-cymene or biphenyl) can catalyze the reduction of prochiral ketones to optically pure alcohols in the presence of a hydride source. Such complexes can achieve the conversion of pyruvate to unnatural http://www.w3.org/1999/xlinkd-lactate in cancer cells. To improve the catalytic performance of these osmium complexes, we have introduced electron-donor and electron-acceptor substituents (R) into thepara(R1) ormeta(R2) positions of the chiral R-phenyl-sulfonyl-diphenylethylenediamine (R-PhDPEN) ligands and explored the reduction of quinones, potential biological substrates, which play a major role in cellular electron transfer chains. We show that the series of [OsII(η6-arene)(R-PhDPEN)] derivatives exhibit high turnover frequencies, enantioselectivities (>92%), and conversions (>93%) for the asymmetric transfer hydrogenation (ATH) of acetophenone-derived substrates and reduce duroquinone and menadione to their di-alcohol derivatives. Modeling of the catalysis using density functional theory (DFT) calculations suggests a mechanism involving formic acid deprotonation assisted by the catalyst amine groups, phenyl-duroquinone stacking, hydride transfer to OsII, possible CO2coordination, and tilting of the η6-arene ring, followed by hydride transfer to the quinone. These findings not only reveal subtle differences between Ru(II) and Os(II) catalysts, but also introduce potential biological applications.
CATALYSTS
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Page/Page column 31-34, (2020/12/11)
A compound, e.g. a diamine ligand, represented by the following general formula (1): (Formula (1)) wherein each * represents an asymmetric carbon atom; X represents a group selected from one of an ester (e.g. a t-butyl ester); a thioester; an amide; a heterocyclic moiety (e.g. a five-membered heterocyclic ring) comprising one or more of O, S, Se, and/or P (e.g. a furan, a tetrahydrofuran, a thiophene, an isoxazole, a bromo-furan, or a thiazole); a moiety (e.g. a five-membered heterocyclic ring) comprising a nitrogen atom, wherein the nitrogen atom is protected with a protecting group containing an electron-withdrawing group, preferably the protecting group is selected from one of a carbamate protecting group, an amide protecting group, an aryl sulphonamide protecting group, or an alkyl sulphonamide protecting group; and optionally X may additionally comprise a solid support, e.g. a polymeric or a silica particle; Y represents or is CtT'T'' where 't' is 0 or 1 and when 't' is 1 T' and T'' may individually represent a substituent, e.g. if t is 1, T' and/or T'' may each be hydrogen or deuterium atom, or a halogen atom; for example, Y may represent a carbon atom comprising two further substituents; Z represents a hydrogen atom or a deuterium atom; R1 represents an alkyl group (e.g. a functionalised alkyl group) preferably having between 1 to 100 carbon atoms, for example, between 1 to 30 carbon atoms (e.g. 1 to 20 carbon atoms, or 1 to 10 carbon atoms), a halogenated alkyl group preferably having between 1 to 100 carbon atoms (e.g. CF3), for example, between 1 to 30 carbon atoms (e.g. 1 to 20 carbon atoms, or 1 to 10 carbon atoms), an aryl group preferably having between 5 to 100 carbon atoms, e.g. 6 to 30 carbon atoms and optionally having one or more substituents selected from alkyl groups preferably having 1 to 100 carbon atoms, e.g. 1 to 10 carbon atoms, halogenated alkyl groups preferably having 1 to 100 carbon atoms, e.g. 1 to 10 carbon atoms, and/or halogen atoms; or R1 represents a solid support, e.g. a silica particle or a polymeric particle; R2 and R3 each independently represent a group selected from alkyl groups preferably having between 1 to 100 carbon atoms, for example 1 to 20 carbon atoms (e.g. 1 to 10 carbon atoms), aryl groups (e.g. phenyl groups), and cycloalkyl groups preferably having 3 to 8 carbon atoms, the aryl group or phenyl group optionally having one or more substituents selected from alkyl groups preferably having between 1 to 100 carbon atoms, e.g. between 1 to 20 carbon atoms (e.g. 1 to 10 carbon atoms), alkoxy groups preferably having between 1 to 100 carbon atoms, for example, between 1 to 20 carbon atoms (e.g. 1 to 10 carbon atoms), and halogen atoms, and each hydrogen atom of the cycloalkyl groups being optionally replaced by an alkyl group preferably having between 1 to 100 carbon atoms, e.g. 1 to 20 carbon atoms (e.g. 1 to 10 carbon atoms), or R1 represents a polyethylene glycol (PEG) moiety having the formula C2nH4n+2On+1 wherein n is an integer between 1 and 100; or R2 and R3 form a ring together with carbon atoms to which R2 and R3 are bonded; R4 represents a hydrogen atom or a deuterium atom.
