10264-55-8Relevant articles and documents
Titanium-catalyzed cascade carboalumination of dienes and trienes
Negishi, Ei-Ichi,Jensen, Michael D.,Kondakov, Denis Y.,Wang, Shan
, p. 8404 - 8405 (1994)
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Enantioselectivity switch in copper-catalyzed conjugate addition reactions under the influence of a chiral N-heterocyclic carbene-silver complex
Matsumoto, Keitaro,Nakano, Yuki,Shibata, Naoatsu,Sakaguchi, Satoshi
, p. 7755 - 7759 (2016)
The asymmetric 1,4-addition of Et2Zn to 2-cyclohexen-1-one using a Cu(i) salt/N-heterocyclic carbene (NHC)-Ag complex catalytic system afforded optically active 3-ethylcyclohexanone. The reversal of enantioselectivity using the same catalytic s
Tropanes as scaffolds for phosphorus-olefin ligands and their application in asymmetric catalysis
Vlahovic, Sandra,Schaedel, Nicole,Tussetschlaeger, Stefan,Laschat, Sabine
, p. 1580 - 1590 (2013)
Tropane-derived phosphorus-olefin hybrid ligands bearing various combinations of P-units (chiral BINOL-derived units/achiral PPh 2-units) with a tropene skeleton (chiral/achiral) have been synthesized and used in Cu-catalysed conjugate 1,4-addi
Enantioselective conjugate addition of dialkylzinc to cyclic enones catalyzed by chiral binaphthyldiamine-copper(I) complexes
Hatano, Manabu,Asai, Takafumi,Ishihara, Kazuaki
, p. 8590 - 8594 (2007)
The enantioselective conjugate addition of dialkylzinc (R2Zn) to cyclic enones was examined using chiral binaphthyldiamine-copper(I) catalysts. Under the present reaction conditions, chiral C2-symmetric [RZn(II)]2-diamine-
Cu-catalyzed asymmetric conjugate addition of dialkylzincs to enones using a (±)- trans -1,2-cyclohexanediamine-based bis(NHC) derived from l -leucinol
Kamihigashi, Shun,Shibata, Naoatsu,Sakaguchi, Satoshi
, p. 2933 - 2937 (2014)
A hydroxyamide-functionalized azolium salt as the precursor of a (±)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand was designed and synthesized from readily accessible l-leucinol. The combination of a Cu salt with this chiral ligand precursor promote
Enantioselective conjugate addition of diethylzinc to cyclic enones with chiral aryl diphosphite-copper catalysts
Yan, Ming,Chan, Albert S. C.
, p. 6645 - 6648 (1999)
A series of C2-symmetric aryl diphosphites based on chiral binaphthol were prepared and their copper complexes were found to be efficient catalysts for the conjugate addition of diethylzinc to cyclic enones. Good enantioselectivities (up to 89.8 and 88.7% ee, respectively) were obtained in the conjugate addition of diethylzinc to 2-cyclohexenone and 2- cyclopentenone.
Highly enantioselective transfer hydrogenation of α,β- unsaturated ketones
Martin, Nolwenn J. A.,List, Benjamin
, p. 13368 - 13369 (2006)
We describe an efficient and highly enantioselective conjugate transfer hydrogenation of α,β-unsaturated ketones that is catalyzed by a salt made from tert-butyl valinate and a recently introduced powerful chiral phosphoric acid catalyst (TRIP). Copyright
Asymmetric catalytic intramolecular hydroacylation of 4-substituted pent-4-enals to β-substituted cyclopentanones
Barnhart, Richard W.,McMorran, David A.,Bosnich
, p. 589 - 590 (1997)
The catalyst, [Rh(S,S-Me-duphos)(acetone)2]+, rapidly and efficiently converts 4-substituted pent-4-enals bearing primary and secondary substituents to the corresponding cyclopentanones and for a variety of substituents the ee was found to range from 93 to 96% at 25°C.
Application of chiral ionic liquids in the copper catalyzed enantioselective 1,4-addition of diethylzinc to enones
Malhotra, Sanjay V.,Wang, Yun
, p. 1032 - 1035 (2006)
Copper catalyzed enantioselective addition of diethylzinc to various enones has been achieved in the presence of a new class of chiral ionic liquid (ChirILs) derived from α-pinene. This first study on the application of ChirILs for the title reaction show
New chiral oxazoline-phosphite ligands for the enantioselective copper- catalyzed 1,4-addition of organozinc reagents to enones
Escher, Iris H.,Pfaltz, Andreas
, p. 2879 - 2888 (2000)
A series of new P,N-ligands with a binaphthyl and an oxazoline moiety were prepared, which are efficient ligands for the enantioselective copper- catalyzed 1,4-addition of organozinc reagents to enones. Increasing the steric bulk in the 3,3'-position of binaphthyl from an H to a biphenylyl moiety improved the ee from 65 to 94% in the reaction of diethylzinc with cyclopentenone. (C) 2000 Elsevier Science Ltd.
The Cu-catalyzed asymmetric conjugate addition with chiral diphosphite ligands derived from D-(-)-tartaric acid
Pang, Zeng-Bo,Tian, Mi,Li, Hai-Feng,Wang, Lai-Lai
, p. 618 - 627 (2017)
A series of diphosphite ligands, which were derived from D-(-)-tartaric acid, have been synthesized and successfully applied in the Cu-catalyzed asymmetric conjugate addition of organozincs to enones. There was a synergic effect between the stereogenic ce
Chiral phosphine-phosphite ligands in the enantioselective 1,4-addition of Grignard reagents to α,β-unsaturated carbonyl compounds
Naeemi, Qaseem,Robert, Tobias,Kranz, Darius P.,Velder, Janna,Schmalz, Hans-Guenther
, p. 887 - 892 (2011)
A library of chiral phosphine-phosphite ligands was evaluated in the Cu-catalyzed asymmetric 1,4-addition of Grignard reagents to cyclopentenone, cycloheptenone and 5,6-dihydro-2H-pyran-2-one. TADDOL-based ligands 1a and 1b with a bulky substituent at the
Synthesis of novel cyclohexanediol-derived chiral phosphite ligands and their application in the Cu-catalyzed conjugate addition of organozinc to cyclic enones
Pang, Zeng-Bo,Li, Hai-Feng,Wang, Lai-Lai
, p. 271 - 276 (2016)
A series of novel chiral diphosphite ligands have been synthesized from (1R,2R)-trans-1,2-cyclohexanediol, (1S,2S)-trans-1,2-cyclohexanediol, racemic trans-1,2-cyclohexanediol and chlorophosphoric acid diary ester, and were successfully employed in the Cu
Synthesis of diphosphite ligands derived from glucopyranoside and their application in the Cu-catalyzed asymmetric 1,4-addition of organozinc to enones
Zhao, Qing-Lu,Tse, Man Kin,Wang, Lai-Lai,Xing, Ai-Ping,Jiang, Xianxing
, p. 2788 - 2793 (2010)
Novel chiral diphosphite ligands derived from glucopyranoside and H 8-binaphthol were synthesized, and successfully employed in the Cu-catalyzed asymmetric 1,4-addition of organozinc reagents dimethylzinc, diethylzinc, and diphenylzinc to cycli
Enantioselective conjugate addition of diethylzinc to enones catalyzed by a copper complex of chiral aryl diphosphite
Yan, Ming,Yang, Li-Wei,Wong, Kwok-Yin,Chan, Albert S. C.
, p. 11 - 12 (1999)
The 1,4-conjugate addition of diethylzinc to cyclohex-2-enone and cyclopent-2-enone catalyzed by a copper complex of a chiral aryl diphosphite gave the desired products with 90.2 and 76.6% ee respectively.
Synthesis of copper(I) complexes of N-heterocyclic carbene-phenoxyimine/ amine ligands: Structures of mononuclear copper(II), mixed-valence copper(I)/(II), and copper(II) cluster complexes
Simonovic, Stevan,Whitwood, Adrian C.,Clegg, William,Harrington, Ross W.,Hursthouse, Michael B.,Male, Louise,Douthwaite, Richard E.
, p. 1786 - 1795 (2009)
Copper(I) bromide complexes (2a and 2b) of NHC-phenol-imine ligand precursors {3-[(1R,2R)-2-{[1-(3,5-di-tert-butyl-2-hydroxyphenyl)meth-(E)- ylidene] amino}cyclohexyl] -1-iso-propyl-4-phenyl-3H-imidazol-1-ium bromide (1a) and 3-[(1R,2R)-2-{[1-(2-hydroxyphenyl)meth-(E)-ylidene] amino}-cyclohexyl] -1-isopropyl-4-phenyl-3H-imidazol-1-ium bro-mide (1b), respectively} have been prepared. Complexes 2aand 2b exhibit copper coordination only through the carbenecarbon atom (C) and do not spontaneously eliminate HBr togive additional phenoxyimine (NO) bonds, which is attrib-uted to intramolecular hydrogen bonding. Crystallisation of2a and 2b gives 2a-and 2b-, respectively, that contain (C) copper(I) bromide and (NO)2 copper(II) coordination. Com-plex 2b-also exhibits intermolecular CuIBr interactions giv-ingaCu2Br2 bridge that links two molecules of 2b resulting in an ellipse motif. Reduction of the ligand precursor iminegroup of 1a allows synthesis of silver(I) and copper(I) NHC-phenolamine complexes 6 and 7, respectively, that also retainthe phenol hydrogen atom. Attempts to selectively prepare2a-gave a copper(II) complex 9 that exhibits an (NO)2CuIIstructure with pendant imidazolium salt groups. Reaction be-tween the silver(I) bromide derivative of 1a and CuCl2·2H2Ogives a complex derived from a Cu6(O)(OH)4Cl3 core and two(NO) and one (CNO) ligands, respectively. The use of 2a and7 as precatalysts for 1,4-conjugate addition to enones andaziridination of alkenes was studied, showing that, whilstboth catalysts are active, enantioselectivities are low, whichis attributed to the lack of Cu-(NO) coordination. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009.
New bis(1-ferrocenylethyl)amine-derived monodentate phosphoramidite ligands for highly enantioselective copper-catalyzed 1,4-conjugate addition
Zou, Dong-Yun,Duan, Zheng-Chao,Hu, Xiang-Ping,Zheng, Zhuo
, p. 235 - 239 (2009)
A new family of chiral bis(1-ferrocenylethyl)amine-derived monodentate phosphoramidite ligands has been prepared and successfully applied in the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to a variety of α,β-unsaturated compounds, in wh
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.
