- Palladium-catalyzed diastereoselective cross-coupling of two aryl halidesviaC-H activation: synthesis of chiral eight-membered nitrogen heterocycles
-
A method for the synthesis of enantiopure eight-membered nitrogen heterocycles has been developed through diastereoselective cross-coupling of 2-iodobiphenyls with 2-bromobenzylamines. The products represent a novel type of chiral scaffold, which feature easy modification and high configurative stability and have the potential to be applied in asymmetric synthesis. Palladacycles that were formedviathe C-H activation of 2-iodobiphenyls should act as the intermediates. The reaction provides a new strategy for the synthesis of medium-sized ring compounds.
- Cheng, Cang,Zuo, Xiang,Tu, Dongdong,Wan, Bin,Zhang, Yanghui
-
supporting information
p. 2939 - 2942
(2021/03/24)
-
- ACCESS TO CHIRAL BISPHENOL (BPOL) LIGANDS THROUGH DESYMMETRIZING ASYMMETRIC ORTHO-SELECTIVE MONO-HALOGENATION
-
The subject invention pertains to a method of halogenating phenols, yielding a range of halogenated phenols with enantiomeric ratio of up to 99.5:0.5. In certain embodiments, the subject invention pertains to a method of asymmetric halogenation of bisphen
- -
-
Paragraph 0011; 0047
(2021/10/02)
-
- Novel bispidine-monoterpene conjugates—Synthesis and application as ligands for the catalytic ethylation of chalcones
-
A number of new chiral bispidines containing monoterpenoid fragments have been ob-tained. The bispidines were studied as ligands for Ni-catalyzed addition of diethylzinc to chalcones. The conditions for chromatographic analysis by HPLC-UV were developed,
- Dalinger, Alexander I.,Kalinin, Mikhail A.,Kuranov, Sergey O.,Munkuev, Aldar A.,Okhina, Alina A.,Ottenbacher, Roman V.,Patrusheva, Oxana S.,Ponomarev, Konstantin Y.,Rogachev, Artem D.,Salakhutdinov, Nariman F.,Suslov, Evgeniy V.,Vatsadze, Sergey Z.,Volcho, Konstantin P.
-
-
- Mechanistic-Insight-Driven Rate Enhancement of Asymmetric Copper-Catalyzed 1,4-Addition of Dialkylzinc Reagents to Enones
-
The combination of [Cu(MeCN)4]TFA·TFAH (TFA = O2CCF3) with Feringa's phosphoramidite ligand (LA) provides an exceptionally active (0.75 mol %) catalyst for asymmetric conjugate additions of ZnR2 (R = Et and Me at -40 to -80 °C) to enones. Kinetic and other studies of the addition of ZnEt2 to cyclohex-2-en-1-one indicate a transition state stoichiometry composition of (ZnEt2)3(enone)4Cu2(LA)3 that is generated by transmetalation from Et2Zn(enone)2. Catalyst genesis is significantly slower than turnover (which has limited previous attempts to attain useful kinetic data); in the initial stages, varying populations of catalytically inactive, off-cycle, species are present. These issues are overcome by a double-dose kinetic analysis protocol. A rest state of [LACu(Et)(μ-TFA)(μ-{(enone)(ZnEt)2(enolate)})CuLA2]+ (through the equivalence of enolate = enone + ZnEt2) is supported by DFT studies (ωB97X-D/SRSC). Rate-determining ZnEt2(enone)2 transmetalation drives the exceptionally high catalytic activity of this system.
- Lewis, William,Nouch, Ryan,Robinson, David,Willcox, Darren,Woodward, Simon
-
supporting information
(2020/03/13)
-
- Catalytic Asymmetric Transfer Hydrogenation of trans-Chalcone Derivatives Using BINOL-derived Boro-phosphates
-
Chiral phosphoric-acid-catalyzed asymmetric reductions of trans-chalcones have been investigated in this work. A BINOL-derived boro-phosphate-catalyzed asymmetric transfer hydrogenation of the carbon-carbon double bond of trans-chalcone derivatives employing borane as a hydride source was realized. This methodology provides a convenient procedure to access chiral dihydrochalone derivatives in high yields and with high enantioselectivities under mild conditions.
- Na, Fei,Lopez, Susana S.,Beauseigneur, Alice,Hernandez, Lucas W.,Sun, Zhuoxin,Antilla, Jon C.
-
p. 5953 - 5957
(2020/08/12)
-
- Enantioselective conjugate hydrosilylation of α,β-unsaturated ketones
-
Enantioselective conjugate hydrosilylation of β,β-disubstituted α,β-unsaturated ketones was realized. In the presence of a chiral picolinamide-sulfonate Lewis base catalyst, the reactions provided various chiral ketones bearing a chiral center at the β-po
- Yang, Huan,Weng, Guanglin,Fang, Dongmei,Peng, Changjiang,Zhang, Yuanyuan,Zhang, Xiaomei,Wang, Zhouyu
-
p. 11627 - 11633
(2019/04/30)
-
- EBINOL axial chiral compound as well as synthesis method and application thereof
-
The invention belongs to the field of axial chiral compounds, and discloses an EBINOL axial chiral compound. The EBINOL axial chiral compound has the following general formula(the formula is shown inthe description), wherein R and R are respectively
- -
-
Paragraph 0238; 0254-0257
(2019/08/02)
-
- Enantioselective Cu-catalyzed 1,4-additions of organozinc and Grignard reagents to enones: Exceptional performance of the hydrido-phosphite-ligand BIFOP-H
-
Enantioselective Cu(I),(II)-(i.e. CuCl, CuCl2, Cu(OTf)2)-catalyzed 1,4-additions of organozinc, i.e. (Et, Me)2Zn, and Grignard reagents, i.e. (Et, Me)MgBr, to chalcone, cyclohexenone and chromone are studied, employing fencholate-based phosphorus ligands, e.g. biphenyl-2,2′-bisfenchyl hydrido phosphite = BIFOP-H. The CuCl·BIFOP-H-catalyzed 1,4-addition of Et2Zn to chalcone yields up to 93% and 99% ee, exceeding established BINOL- and TADDOL-based phosphoramidite ligands. Remarkably, CuCl performs better in 1,4-additions to chalcone (CuCl: 76% ee; Cu(OTf)2: 49% ee; CuCl2: 42% ee) while Cu(OTf)2 performs better in 1,4-additions to cyclohexenone (Cu(OTf)2: 65% ee; CuCl: 20% ee). The computation of the reaction pathway is done for the CuI-catalyzed 1,4-addition to chalcone (CuII will be in situ reduced to CuI by a reagent, TPSS-D3(BJ)/def2-TZVP//B3LYP-D3(BJ)/def2-SVP) for six different model ligands, i.e. (MeO)2P-X (X = H, F, Me, OMe, NMe2 and PMe3). Origins of enantioselectivities are analyzed (M06-2X-D3/def2-TZVP//B3LYP-D3(BJ)/def2-SVP) for transition structures of the 1,4-methylation of chalcone with the Cu·BIFOP-H catalyst and explain the experimentally observed (R)-enantiomer's preference.
- Brüllingen, Eric,Neud?rfl, J?rg-Martin,Goldfuss, Bernd
-
supporting information
p. 4787 - 4799
(2019/03/26)
-
- Copper-catalyzed enantioselective 1,4-conjugate addition of dialkylzinc reagents to α,β- and α,β,γ,δ-unsaturated ketones
-
An enantioselective Cu(II)-catalyzed conjugate addition of dialkylzinc reagents to α,β- or α,β,γ,δ-unsaturated ketones with chiral cyclohexane-based amidophosphine ligands was developed. With 2 mol% of Cu(OAc)2·H2O/L5, the conjugate
- Rexiti, Rukeya,Lu, Jian,Sha, Feng,Wu, Xin-Yan
-
p. 3596 - 3604
(2019/06/04)
-
- Lewis Base-Catalyzed Enantioselective Conjugate Reduction of β,β-Disubstituted α,β-Unsaturated Ketones with Trichlorosilane: E/ Z-Isomerization, Regioselectivity, and Synthetic Applications
-
The chiral bisphosphine dioxide-catalyzed asymmetric conjugate reduction of acyclic β,β-disubstituted α,β-unsaturated ketones with trichlorosilane affords saturated ketones having a stereogenic carbon center at the carbonyl β-position with high enantioselectivities. Because the E/Z-isomerizations of enone substrates occur concomitantly, reduction products with the same absolute configurations are obtained from either (E)- or (Z)-enones. Conjugate reduction is accelerated in the presence of an electron-rich aryl group at the β-position of the enone owing to its carbocation-stabilizing ability. Computational studies were also conducted in order to elucidate the origin of the observed enantioselectivity. The regio- and enantioselective reductions of dienones were realized and applied to the syntheses of ar-turmerone, turmeronol A, mutisianthol, and jungianol, which are optically active sesquiterpenes.
- Sugiura, Masaharu,Ashikari, Yasuhiko,Takahashi, Yuka,Yamaguchi, Koki,Kotani, Shunsuke,Nakajima, Makoto
-
p. 11458 - 11473
(2019/10/11)
-
- Enantiopure sulfoximines-catalyzed 1, 4-additions to 2-en-ketone
-
An efficient chiral catalyst procedure for the preparation of β-chiral ketone via the 1, 4-additions reaction of 2-en-ketone has been developed using enantiopure sulfoximines modified with functional groups as ligands. The carefully design and synthesized
- Zhao, Hongwei,Han, Hui,Yang, Hengquan,wang, Li
-
p. 210 - 213
(2018/06/26)
-
- Heterogeneous catalytic 1,4-addition of arylmagnesium compounds to chalcones
-
Copper(II) on a 4 ? molecular sieve support catalyses the chemoselective addition of alkyl- and arylmagnesium halides to chalcones. Only the 1,4-addition products were obtained in high yields.
- Juhász, Kinga,Hell, Zoltán
-
supporting information
p. 3136 - 3138
(2018/07/13)
-
- The Cu-catalyzed asymmetric conjugate addition with chiral diphosphite ligands derived from D-(-)-tartaric acid
-
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
- Pang, Zeng-Bo,Tian, Mi,Li, Hai-Feng,Wang, Lai-Lai
-
supporting information
p. 618 - 627
(2017/03/15)
-
- Highly efficient synthesis of chiral aromatic ketones: Via Rh-catalyzed asymmetric hydrogenation of β,β-disubstituted enones
-
A succinct and efficient protocol was developed for the synthesis of chiral aromatic ketones via asymmetric hydrogenation of β,β-disubstituted enones with rhodium catalysts based on chiral bisphosphine thiourea ligands. A series of substrates (17 examples) was smoothly catalyzed to afford the corresponding chiral aromatic ketones in high conversions (>99%) with excellent enantioselectivities (up to 96% ee).
- Zhang, Tao,Jiang, Jun,Yao, Lin,Geng, Huiling,Zhang, Xumu
-
p. 9258 - 9261
(2017/08/22)
-
- Enantioselective copper(II)-catalyzed conjugate addition of diethylzinc to β-substituted enones utilizing BINOL-based phosphoramidite ligands
-
A family of new chiral phosphoramidite ligands based on 3,3′-disubstituted (S)-BINOL have been successfully synthesized. The chiral phosphoramidite ligands were subsequently applied to the copper(II)-catalyzed enantioselective addition of diethylzinc to β
- Zhao, Wenxian,Wang, Tao,Zhao, Ruijuan,Xie, Huanping,Liu, Lantao
-
p. 157 - 162
(2018/10/06)
-
- Copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones with chiral sulfoxide-phosphine ligands
-
The copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones was achieved with chiral sulfoxide-phosphine (SOP) ligands. This process showed good functional group tolerance and gave the 1, 4-adducts with excellent enantioselec
- Yang, Tingting,Zhang, Yongling,Cao, Peng,Wang, Min,Li, Li,Li, Dong,Liao, Jian
-
p. 2707 - 2711
(2016/05/10)
-
- Enantioselective synthesis of planar-chiral 1,11-dioxa[11]paracyclophane-derived phosphoramidites and their use as chiral ligands
-
A library of bench-stable planar-chiral 1,11-dioxa[11]paracyclophane-derived phosphoramidites was synthesized by a three step procedure: enantioselective ortho-lithiation, reductive amination and coupling with phosphorochloridites. The efficacy of these phosphoramidite as chiral ligands was tested in the Pd-catalyzed allylic alkylation of dimethyl malonate and the Cu-catalyzed ethylation of chalcone under the reported conditions, with moderate enantioselectivity being obtained.
- Hazra, Madhurima,Kanyiva, Kyalo Stephen,Shibata, Takanori
-
p. 1081 - 1087
(2016/10/11)
-
- Nickel-catalysed cyclopropanation of electron-deficient alkenes with diiodomethane and diethylzinc
-
In the presence of a nickel catalyst, the cyclopropanation of electron-deficient alkenes with diiodomethane and diethylzinc is drastically accelerated. A wide range of cyclopropyl ketones, esters and amides can be accessed under these conditions.
- Xu, Jin,Samsuri, Nazurah Binte,Duong, Hung A.
-
p. 3372 - 3375
(2016/02/27)
-
- Paracyclophane-derived monodentate phosphoramidite ligands for copper-catalyzed asymmetric conjugate addition of diethylzinc to substituted chalcones
-
Copper-catalyzed asymmetric conjugate addition of diethylzinc to chalcones could be realized by using [2.2]paracyclophane-derived monodentate phosphoramidite ligands. The excellent yield and enantioselectivity (up to 98% yield and 95% enantiomeric excess) could be realized with low catalyst loading of 1.0 mol % and low ligand loading of 1.2%.
- Han, Lei,Lei, Yang,Xing, Ping,Zhao, Xiao-Long,Jiang, Biao
-
p. 3752 - 3757
(2015/05/05)
-
- Highly efficient conjugate additions of diethylzinc to enones promoted by chiral aziridine alcohols and aziridine ethers
-
Abstract Chiral heteroorganic N-trityl aziridine alcohols and aziridine ethers have proven to be highly efficient catalysts in enantioselective conjugate diethylzinc additions to enones, namely chalcone and 2-cyclohexen-1-one providing the desired chiral
- Jarzyński, Szymon,Rachwalski, Micha?,Pieczonka, Adam M.,Wujkowska, Zuzanna,Le?niak, Stanis?aw
-
p. 924 - 927
(2015/09/01)
-
- C2-symmetric functionalized azolium salt from serine ester for Cu-catalyzed asymmetric conjugate addition reaction
-
C2-symmetric ester-amide functionalized azolium salt was synthesized from readily available α-amino ester such as L-serine methyl ester. The combination of a Cu salt and the chiral azolium salt promoted the asymmetric conjugate addition reactio
- Kondo, Junko,Harano, Ayako,Dohi, Kenta,Sakaguchi, Satoshi
-
-
- Sugar-based monodentate phosphoramidite ligands for Cu-catalyzed enantioselective conjugate addition to enones
-
In this paper we present new, monodentate phosphoramidite ligands based on amines derived from the easy available monosaccharide d-xylose and BINOLs. Ligands were used for copper-catalyzed conjugate addition to acyclic and cyclic enones. The highest enantioselectivity achieved in this study was 77% ee for the conjugate addition to trans-chalcone, which is comparable to the best results published to date for phosphoramidite ligands based on carbohydrate-derived amines.
- Bauer, Tomasz,Majdecki, MacIej,Jurczak, Janusz
-
p. 1930 - 1939
(2013/04/10)
-
- Functionalized BINOL-mono-PHOS for multinuclear Cu-catalysts in asymmetric conjugate addition of organozinc reagents
-
Functionalization of BINOL-mono-PHOS achieved the Cucatalyzed highly asymmetric conjugate addition of organozinc reagents to enones. The incorporation of a bulky hydroxy group at the 3'-position of BINOL-mono-PHOS dramatically improved the yield and enantioselectivity. The present novel BINOL-mono-PHOS ligands are effective in the Cu-catalyzed asymmetric conjugate addition of organozinc reagents in both acyclic enones and cyclohexenone.
- Endo, Kohei,Yakeishi, Sayuri,Hamada, Daisuke,Shibata, Takanori
-
supporting information
p. 547 - 549
(2013/06/05)
-
- BINAM- mono -PHOS as new entry for multinuclear copper catalysts in asymmetric conjugate addition of organozinc reagents
-
The readily functionalized ligands, BINAM-PHOS, participate in the copper-catalyzed asymmetric conjugate addition of organozinc reagents to enones. The incorporation of benzoyl derivatives on nitrogen atoms was crucial to promote the reaction. Notably, BI
- Endo, Kohei,Takayama, Ryotaro,Shibata, Takanori
-
p. 1155 - 1159
(2013/06/27)
-
- Highly efficient conjugate addition of diethylzinc to enones catalyzed by chiral ligands derived from (S)-mandelic acid
-
Diastereomerically pure heteroorganic catalysts built on the chiral scaffold of (S)-(+)-mandelic acid and containing secondary hydroxyl and aziridine moieties, have proven to be highly efficient for the enantioselective conjugate diethylzinc addition to c
- Rachwalski, Michal,Jarzynski, Szymon,Lesniak, Stanislaw
-
p. 1117 - 1119
(2013/10/08)
-
- Palladium-catalyzed diorganozinc conjugate additions to enones: Preparative and computational studies
-
The Pd-catalyzed conjugate addition of diorganozinc reagents to α,β-unsaturated carbonyl compounds has been applied to a variety of enone substrates, both cyclic and acyclic, encompassing various combinations of aryl and alkyl substitution, in combination with diorganozinc reagents incorporating alkyl (Me, linear and branched) or Ph groups. While both Pd 0 and PdII complexes have been found to be competent precatalysts, reaction yields are strongly dependent on the relative amounts of Pd to phosphane ligand. Thus, a 1:1 Pd/P ratio is well tolerated, but going to Pd/P = 1:2 leads to poor conversions and yields. A calculated Pd 0-mediated pathway involving an unusual oxidative addition step with simultaneous transmetalation, followed by reductive elimination, has been found to be compatible with the observed phosphane effect. A phosphane dependence is found in the Pd0-catalyzed diorganozinc conjugate addition to enones, which is compatible with a calculated reaction pathway proceeding through simultaneous oxidative addition/transmetalation followed by reductive elimination. Copyright
- Lorenzo, Paula,Aurrecoechea, Jose M.,De Lera, Angel R.,Alvarez, Rosana
-
p. 2621 - 2626
(2013/06/04)
-
- Modulation of multifunctional N,O,P ligands for enantioselective copper-catalyzed conjugate addition of diethylzinc and trapping of the zinc enolate
-
In this work, we have successfully synthesized a new family of chiral Schiff base-phosphine ligands derived from chiral binaphthol (BINOL) and chiral primary amine. The controllable synthesis of a novel hexadentate and tetradentate N,O,P ligand that contains both axial and sp3-central chirality from axial BINOL and sp3-central primary amine led to the establishment of an efficient multifunctional N,O,P ligand for copper-catalyzed conjugate addition of an organozinc reagent. In the asymmetric conjugate reaction of organozinc reagents to enones, the polymer-like bimetallic multinuclear Cu-Zn complex constructed in situ was found to be substrate-selective and a highly excellent catalyst for diethylzinc reagents in terms of enantioselectivity (up to >99 % ee). More importantly, the chirality matching between different chiral sources, C2-axial binaphthol and sp3-central chiral phosphine, was crucial to the enantioselective induction in this reaction. The experimental results indicated that our chiral ligand (R,S,S)-L1- and (R,S)-L4-based bimetallic complex catalyst system exhibited the highest catalytic performance to date in terms of enantioselectivity and conversion even in the presence of 0.005 mol % of catalyst (S/C=20 000, turnover number (TON)=17 600). We also studied the tandem silylation or acylation of enantiomerically enriched zinc enolates that formed in situ from copper-L4-complex-catalyzed conjugate addition, which resulted in the high-yield synthesis of chiral silyl enol ethers and enoacetates, respectively. Furthermore, the specialized structure of the present multifunctional N,O,P ligand L1 or L4, and the corresponding mechanistic study of the copper catalyst system were investigated by 31P NMR spectroscopy, circular dichroism (CD), and UV/Vis absorption. Match maker: The chiral bimetallic multinuclear Cu-Zn complex that contains a novel phosphine ligand and bears matching axial and sp3-central chirality from binaphthol and chiral amine was found to be a highly efficient catalyst in the enantioselective conjugate addition of an organic zinc reagent. Copyright
- Ye, Fei,Zheng, Zhan-Jiang,Deng, Wen-Hui,Zheng, Long-Sheng,Deng, Yuan,Xia, Chun-Gu,Xu, Li-Wen
-
supporting information
p. 2242 - 2253
(2013/09/23)
-
- Ferrocene phosphane-carbene ligands in Cu-catalyzed enantioselective 1,4-additions of Grignard reagents to α,β-unsaturated carbonyl compounds
-
Chiral ferrocene phosphane-carbenes are good ligands for the copper-catalyzed 1,4-addition of Grignard reagents to various Michael acceptors. The products were obtained in high enantiomeric purity (up to e.r. = 95:5) and excellent regioselectivity (r.r. =
- Csizmadiová, Jana,Me?iarová, Mária,Almássy, Ambroz,Horváth, Branislav,?ebesta, Radovan
-
-
- Multinuclear Cu-catalysts based on SPINOL-PHOS in asymmetric conjugate addition of organozinc reagents
-
Multinuclear Cu/Zn complex-catalyzed efficient asymmetric conjugate addition of organozinc reagents to acyclic and cyclic enones has been developed in the presence of a wide variety of regioisomeric chiral diols bearing phosphorus moieties as ligands. The
- Endo, Kohei,Hamada, Daisuke,Yakeishi, Sayuri,Ogawa, Mika,Shibata, Takanori
-
supporting information; experimental part
p. 2342 - 2345
(2012/06/29)
-
- Enantioselective copper-catalyzed 1,4-addition of dialkylzincs to enones using a novel N,N,P-Cu(II) complex
-
Enantioselective copper-catalyzed 1,4-additions of dialkylzincs to enones were carried out in the presence of 1 mol % of Cu(OTf)2 and 2.5 mol % of an N,N,P-ligand possessing a tert-butyl group at the adjacent position of the nitrogen of pyridin
- Ebisu, Yasuhiro,Kawamura, Kenjiro,Hayashi, Masahiko
-
experimental part
p. 959 - 964
(2012/09/25)
-
- Switchable stereoselectivity: The effects of substituents on the D 2-symmetric biphenyl backbone of phosphoramidites in copper-catalyzed asymmetric conjugate addition reactions with triethylaluminium
-
A highly enantioselective copper-catalyzed conjugate addition with triethylaluminium was developed using phosphoramidite ligands bearing a D 2-symmetric biphenyl backbone. For these ligands we demonstrated that the 3,3',5,5'-substituents on the biphenyl backbone can completely reverse the absolute configuration of the products. Copyright
- Yu, Han,Xie, Fang,Ma, Zhenni,Liu, Yangang,Zhang, Wanbin
-
p. 1941 - 1947
(2012/09/25)
-
- The effects of solvent on switchable stereoselectivity: Copper-catalyzed asymmetric conjugate additions using D2-symmetric biphenyl phosphoramidite ligands
-
A highly enantioselective copper-catalyzed conjugate addition of diethylzinc to acyclic aromatic enones was developed with phosphoramidite ligands bearing a D2-symmetric biphenyl backbone. This type of reaction demonstrated that toluene and THF solvents can completely reverse the absolute configuration of the products, thus simplifying the process of accessing either enantiomer (S: 92% ee, 94% yield; R: 99% ee, 96% yield).
- Yu, Han,Xie, Fang,Ma, Zhenni,Liu, Yangang,Zhang, Wanbin
-
p. 5137 - 5142
(2012/08/07)
-
- Enantioselective conjugate addition of dialkylzincs to α,β- unsaturated enones catalyzed by Ni(acac)2 and (+)-(1S,2R)-7,7- dimethyl-1-morpholinoisonorborneol
-
A mixture of chiral ligand 4 [(+)-MINBOL] and Ni(acac)2 (12.5 and 0.5 mol % respectively) is able to successfully catalyze the enantioselective conjugate 1,4-addition of dialkylzinc to α,β- unsaturated enones in propionitrile to give the corres
- Tseng, Chih-Hao,Hung, Yu-Ming,Uang, Biing-Jiun
-
experimental part
p. 130 - 135
(2012/05/20)
-
- Chiral dinuclear phthalazine bridged bisoxazoline ligands: Synthesis and application in enantioselective Cu-catalyzed conjugate addition of ZnEt 2 to enones
-
A new class of chiral dinuclear ligands with phthalazine bridged bisoxazoline scaffold was designed and prepared in convenient synthetic routes. 1H NMR analysis showed that this class of ligands could coordinate with two metal ions, either same
- Zhang, Liang,Yang, Guoqiang,Shen, Chaoren,Arghib, Sabah,Zhang, Wanbin
-
supporting information; experimental part
p. 2375 - 2378
(2011/05/09)
-
- Enantioselective copper-catalyzed 1,4-addition of dialkylzincs to enones followed by trapping with allyl iodide derivatives
-
Enantioselective copper-catalyzed 1,4-addition of dialkylzincs to enones proceeded in the presence of 0.1 mol% of Cu(OTf)2 and 0.25 mol% of an N,N,P-ligand containing a quinoline moiety to afford the corresponding conjugated adducts in 99%ee. The intermediate zinc enolates were trapped with substituted allyl iodides to give disubstituted ketones with high diastereoselectivity and enantioselectivity.
- Kawamura, Kenjiro,Fukuzawa, Hitomi,Hayashi, Masahiko
-
experimental part
p. 640 - 647
(2011/08/06)
-
- Copper-catalyzed asymmetric conjugate addition of diethylzinc to substituted chalcones using a chiral phosphine ligand
-
A series of chiral phosphine PFAM and phosphine oxide POFAM ligands were studied for the copper-catalyzed asymmetric diethylzinc addition to enones. One of these ligands, PFAM2, was an efficient catalyst with a variety of enones to give conjugate addition
- Dogan, Oezdemir,Bulut, Adnan,Polat, Sava,Ali Tecimer
-
scheme or table
p. 1601 - 1604
(2011/12/22)
-
- Synthesis of novel chiral bidentatephosphite ligands derived from the pyranoside backbone of monosaccharides and their application in the Cu-catalyzed conjugate addition of dialkylzinc to enones
-
A series of novel bidentatephosphite ligands, derived from methyl 3,6-anhydro-α-d-glucopyranoside and chlorophosphoric acid diaryl ester, were easily synthesized. These ligands were successfully employed in the Cu-catalyzed asymmetric conjugate 1,4-additi
- Zhao, Qing-Lu,Wang, Lai-Lai
-
experimental part
p. 1885 - 1890
(2012/02/05)
-
- Synthesis of novel carbohydrate-based chiral P, N ligands and their applications in Cu-catalyzed enantioselective 1, 4-conjugate additions
-
A new type of phosphate-pyridine (P, N) ligand derived from d-glucosamine and BINOL was synthesized and successfully applied in Cu-catalyzed enantioselective conjugate addition of diethylzinc to chalcones for the first time, high yields and enantioselectivities were obtained when the ligand 10a which contains (S)-BINOL was used. The results also showed that the configuration of BINOL at the ligand backbone had remarkable effects on the activities and enantioselectivities.
- Xia, Haijun,Yan, Hua,Shen, Chao,Shen, Fangyi,Zhang, Pengfei
-
experimental part
p. 155 - 158
(2012/03/08)
-
- Pd-catalyzed asymmetric hydrogenation of C=C bond of α,β- unsaturated ketones
-
Homogenous palladium-catalyzed asymmetric hydrogenation of C=C double bond of ,-unsaturated ketones has been -developed by using palladium(II) trifluoroacetate/(S)-7,7-bis-[di(4-methoxyphenyl]phosphino)-1,1-spirobiindane complex [Pd(OCOCF3)2-(S)-An-SDP] as the catalyst under ambient hydrogen pressure and room temperature with up to 89% ee. Georg Thieme Verlag Stuttgart · New York.
- Wang, Duo-Sheng,Wang, Da-Wei,Zhou, Yong-Gui
-
p. 947 - 950
(2011/06/17)
-
- METHOD OF ENANTIOSELECTIVE ADDITION TO ENONES
-
The present invention relates to a method of enantioselective addition to enones, including: reacting R3(CH2)pCH═CR5C(═O)Y(CH2)qR4 with R6ZnR7 in the presen
- -
-
Page/Page column 16; 17
(2011/11/30)
-
- Multinuclear catalyst for copper-catalyzed asymmetric conjugate addition of organozinc reagents
-
(Figure Presented) A whole lot o' metal: An efficient copper-catalyzed asymmetric conjugate addition was achieved using a binol-derived ligand. The catalytic system has a turnover number of 2000, and the excellent cata-lytic performance could be attributed to the generation of a multinuclear complex such as 1. binol = 2, 2'-dihydroxy-l, 1'-binaphthyl.
- Endo, Kohei,Ogawa, Mika,Shibata, Takanori
-
supporting information; scheme or table
p. 2410 - 2413
(2010/06/15)
-
- Chiral phosphanylferrocenecarboxamides with amino acid pendant groups as ligands for Cu-mediated asymmetric conjugate additions of diethylzinc to chalcones - Structural characterisation of precursors to the Cu catalyst
-
A series of chiral phosphanylferrocenecarboxamides was prepared by treatment of either l'-(diphenylphosphanyl)ferrocene-1-carboxylic acid (Hdpf) or its planar-chiral 1,2isomers with amino acid methyl esters in the presence of peptide coupling agents. The compounds were characterised by spectroscopic methods, and the crystal structure of one representative was determined by X-ray diffraction. Catalytic testing of these donors in Cu-catalysed asymmetric conjugate additions of diethylzinc to chalcones revealed that the reaction outcomes were highly sensitive to the ligand structure and the reaction conditions (copper source and solvent), whereas the chalcone substituents (Me, MeO, or Cl in positions 4 or 4') had a less pronounced influence. Compounds based on Hdpf proved to be better ligands than their planarchiral analogues. Under optimised conditions, the reaction with L-valine-Hdpf conjugate, (S)-Ph2PfcCONHCH(CHMe2)CO2Me (fc = ferrocene-1,1'-diyl) and unsubstituted chalcone gave the alkylation product with complete conversion (20 °C/ 4 h) and in 87 % ee. The catalytic behaviour of the amidophosphane ligands was correlated to the results of a model coordination study and the crystal structure of [Cu(Ph2PfcCONHCH 2CO2Me)2](CF3SO3) ·2CHCl3.
- Tauchman, Jiri,Cisarova, Ivana,Stepnicka, Petr
-
experimental part
p. 4276 - 4287
(2010/10/21)
-
- Copper-catalyzed asymmetric 1,4-conjugate addition of dialkylzinc to enones
-
Asymmetric 1,4-conjugation addition of dialkylzinc (diethylzinc and dimethylzinc) to cyclic enones, chalcone and nitroalkenes was achieved by a 25 mol% (R)-6,6'-Br2-BINOL(1f), 25 mol% CuSPh and 100 mol% dicyclohexylmethylamin(Cy2NMe) catalyst system. The Cu(I) catalyst system enables the cyclic enone, chalcone and nitroalkene generality with high enantioselectivity (up to84%ee) and isolated yield (up to 94%) under mild reaction conditions.
- Gou, Shaohua,Ye, Zhongbin,Shi, Leiting,Qing, Dayong,Zhang, Wen,Wang, Yuliang
-
experimental part
p. 517 - 522
(2010/10/18)
-
- Highly enantioselective conjugate addition of diethylzinc to enones usingaziridine-functionalized tridentate sulfinyl ligands
-
Enantiomerically pure tridentate heteroorganic catalysts, containing hydroxyl, sulfinyl, and aziridine moieties, have proven to be highly efficient in the enantioselective conjugate diethylzinc addition to chalcone and cyclohexenone to give the desired pr
- Rachwalski, Michal,Lesniak, Stanislaw,Kielbasinski, Piotr
-
experimental part
p. 1890 - 1892
(2010/11/05)
-
- Synthesis of diphosphite ligands derived from glucopyranoside and their application in the Cu-catalyzed asymmetric 1,4-addition of organozinc to enones
-
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
- Zhao, Qing-Lu,Tse, Man Kin,Wang, Lai-Lai,Xing, Ai-Ping,Jiang, Xianxing
-
experimental part
p. 2788 - 2793
(2011/03/18)
-
- Synthesis of novel diphosphite ligands derived from d-mannitol and their application in Cu-catalyzed enantioselective conjugate addition of organozinc to enones
-
A series of novel chiral diphosphite ligands have been synthesized from d-mannitol derivatives and chlorophosphoric acid diary ester, and were successfully employed in the copper catalyzed enantioselective conjugate addition of organozinc reagents diethyl
- Zhao, Qing-Lu,Wang, Lai-Lai,Xing, Ai-Ping
-
experimental part
p. 2993 - 2998
(2011/03/22)
-
- Heterotopic silver-NHC complexes: From coordination polymers to supramolecular assemblies
-
New coordination polymers based on different combinations of silver atoms and pyridyl-substituted N-heterocyclic carbene moieties are described. The addition of Zn(ii) templates leads to Ag-Zn supramolecular assemblies via selective Zn...N interactions; a process that can be reverted.
- Rubio, Miguel,Siegler, Maxime A.,Spek, Anthony L.,Reek, Joost N.H.
-
supporting information; experimental part
p. 5432 - 5435
(2010/08/05)
-
- Design and synthesis of new chiral pyridine-phosphite ligands for the copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones
-
A series of new chiral pyridine-phosphite ligands have been prepared from (R)-pyridyl alcohols and BINOL-derived chlorophosphite, and successfully employed in the copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones. Using the simple and inexpensive CuBr2 as a precursor, the enantioselective additions to various substituted acyclic enones afforded products in high yields and good enantioselectivities (up to 92% ee).
- Xie, Yinjun,Huang, Hanmin,Mo, Weimin,Fan, Xiangqun,Shen, Zhiqiang,Shen, Zhenlu,Sun, Nan,Hu, Baoxiang,Hu, Xinquan
-
scheme or table
p. 1425 - 1432
(2009/12/04)
-
- Application of Enantiopure 1-(Aminoalkyl)naphthols and 2-(Aminoalkyl) phenols in the Enantioselective Addition of Organozinc to ,-Unsaturated Carbonyl Compounds
-
Several enantiopure 1-(aminoalkyl)naphthols and a 2-(aminoalkyl)phenol were tested as ligands in the Nickel-catalyzed enantioselective addition of organozinc to chalcones.
- Cimarelli, Cristina,Fratoni, Davide,Palmieri, Gianni
-
scheme or table
p. 3184 - 3190
(2009/11/30)
-