- Synthesis of novel C2 and C1 symmetric chiraphos derivatives and their application in palladium-catalyzed miyauramichael reaction
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A new method for the synthesis of C2 and C1 symmetric CHIRAPHOS derivatives and their application in Pd-catalyzed 1,4-addition reaction of an aryl boron compound to an ,¢-unsaturated carbonyl compound (MiyauraMichael reaction) are described. Six CHIRAPHOS congeners are prepared by substitution reactions of (2R,3R)-butane-2,3-diyl ditosylate with metalated phosphineborane adducts and subsequent deprotection of the resulting borane-protected bisphosphines. In the asymmetric MiyauraMichael reaction, the CHIRAPHOS derivative containing 4-tolyl groups showed a higher enantioselectivity than the others including parent CHIRAPHOS.
- Jin, Masayoshi,Nakamura, Masaharu
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- Electrochemical Oxidative C–H Phosphonylation of thiazole derivatives in ambient conditions
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We herein report a direct electrochemical dehydrogenative C–H phosphonylation of thiazoles derivatives with H2 evolution. Employing electricity as the green and sole oxidant, cheap metal as electrode, the anodic oxidation together with cathodic hydrogen evolution process provides a green and efficient strategy for C–H phosphonylation. A diverse range of phosphorus products were constructed under external metal and oxidant-free conditions at ambient temperature, featuring atom economy, simple operation and wide reaction scope.
- Li, Yang,Wu, Lei,Yang, Yan-Tong,Zhu, Jie,Zhu, Peng-Wei
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- Organic photoredox catalytic α-C(sp3)-H phosphorylation of saturated: Aza -heterocycles
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A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Br?nsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.
- Yi, Ming-Jun,Xiao, Teng-Fei,Li, Wen-Hui,Zhang, Yi-Fan,Yan, Pen-Ji,Zhang, Baoxin,Xu, Peng-Fei,Xu, Guo-Qiang
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supporting information
p. 13158 - 13161
(2021/12/16)
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- Cinchona alkali ligand and preparation method and application thereof
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The invention belongs to the field of organic chemical ligands, and particularly relates to a cinchona alkali ligand, which has a structure shown in a general formula I or a tautomer, an enantiomer and a diastereoisomer thereof, in the formula I, R1 is selected from alkyl, alkenyl and -CH = CHPh, R2 is selected from hydrogen, alkyl, phenyl and substituted phenyl, and R is selected from substituted phenyl. The invention also discloses a preparation method and application of the cinchona alkaloid ligand. The ligand disclosed by the invention has advantages in stereoselectivity and reaction efficiency, and a higher ee value and yield can be obtained in an asymmetric reaction.
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Paragraph 0085-0088; 0093-0096; 0128-0129; 0134-0135; ...
(2021/12/31)
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- Development of effective bidentate diphosphine ligands of ruthenium catalysts toward practical hydrogenation of carboxylic acids
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Hydrogenation of carboxylic acids (CAs) to alcohols represents one of the most ideal reduction methods for utilizing abundant CAs as alternative carbon and energy sources. However, systematic studies on the effects of metal-to-ligand relationships on the catalytic activity of metal complex catalysts are scarce. We previously demonstrated a rational methodology for CA hydrogenation, in which CA-derived cationic metal carboxylate [(PP)M(OCOR)]+ (M = Ru and Re; P = one P coordination) served as the catalyst prototype for CA self-induced CA hydrogenation. Herein, we report systematic trial- and-error studies on how we could achieve higher catalytic activity by modifying the structure of bidentate diphosphine (PP) ligands of molecular Ru catalysts. Carbon chains connecting two P atoms as well as Ar groups substituted on the P atoms of PP ligands were intensively varied, and the induction of active Ru catalysts from precatalyst Ru(acac)3 was surveyed extensively. As a result, the activity and durability of the (PP)Ru catalyst substantially increased compared to those of other molecular Ru catalyst systems, including our original Ru catalysts. The results validate our approach for improving the catalyst performance, which would benefit further advancement of CA self-induced CA hydrogenation.
- Saito, Susumu,Wen, Ke,Yoshioka, Shota
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supporting information
p. 1510 - 1524
(2021/06/18)
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- Highly Enantioselective Synthesis of Phosphorus-Containing ?-Benzosultams by Bifunctional Phosphonium Salt-Promoted Hydrophosphonylation
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?-Benzosultam derivatives are potential drug candidates with diverse biological activities. A series of chiral ?-benzosultams bearing phosphorus functionalities was synthesized by catalytic asymmetric hydrophosphonylation in the presence of a bifunctional phosphonium salt catalyst. The desired hydrophosphonylation products were obtained in good yields with high enantioselectivities, and scale-up reactions and further derivations were successfully accomplished. Some control experiments were also conducted to elucidate the plausible reaction mechanism of this chemical transformation.
- Zhang, Song,Feng, Zhenghuai,Jiang, Chunhui,Yu, Xiaojun,Pan, Jianke,Du, Juan,Jiang, Zhiyu,Chen, Yuan,Wang, Tianli
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supporting information
p. 11285 - 11290
(2021/07/02)
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- Manganese-Promoted Regioselective Direct C3-Phosphinoylation of 2-Pyridones
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A highly efficient and regioselective manganese-induced radical oxidative direct C?P bond formation between 2-pyridones and secondary phosphine oxides was developed. The C3-selective phosphinoylation was conveniently achieved through a combination of substoichiometric manganese and persulfate oxidant under mild conditions. Various 3-phosphinoylated pyridone products can be obtained in moderate to high yields. Preliminary mechanistic studies suggest that the reaction is likely to involve a radical pathway induced by catalytically active Mn3+ species.
- Chantarojsiri, Teera,Kittikool, Tanakorn,Phakdeeyothin, Kunita,Yotphan, Sirilata
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supporting information
p. 3071 - 3078
(2021/07/22)
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- Cobaloxime Catalysis for Enamine Phosphorylation with Hydrogen Evolution
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Direct phosphorylation of enamine and enamide with hydrogen evolution was realized via cobaloxime catalysis under visible-light irradiation. Control experiments and spectroscopic studies demonstrated a reductive quenching pathway of cobaloxime catalyst to produce phosphinoyl radical, which underwent cross-coupling with various enamines (and enamides) to give diverse β-phosphinoyl products in good to excellent yields. More interestingly, Z/E mixture of acyclic enamines could convert into single Z-products with good reactivity.
- Lei, Tao,Liang, Ge,Cheng, Yuan-Yuan,Chen, Bin,Tung, Chen-Ho,Wu, Li-Zhu
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supporting information
p. 5385 - 5389
(2020/07/08)
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- Enantioselective hydrophosphinylation of 1-alkenylphosphine oxides catalyzed by chiral strong Br?nsted base
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A catalytic enantioselective addition of diarylphosphine oxides to 1-alkenyl(diaryl)phosphine oxides was achieved by using a chiral ureate as a chiral strong Br?nsted base catalyst. The reaction followed by the reduction of phosphine oxide moieties provid
- Ishikawa, Sho,Kondoh, Azusa,Terada, Masahiro
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supporting information
p. 7814 - 7817
(2020/11/02)
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- Transition Metal-Free Synthesis of α-Aminophosphine Oxides through C(sp3)?P Coupling of 2-Azaallyls
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Radical reactions have been widely applied in C?P bond-forming strategies. Most of these strategies require initiators, transition metal catalysts, or organometallic reagents. Herein, a transition metal-free C(sp3)?P bond formation to prepare α
- Wang, Jing,Deng, Guogang,Liu, Chunxiang,Chen, Zhuo,Yu, Kaili,Chen, Wen,Zhang, Hongbin,Yang, Xiaodong
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supporting information
p. 2268 - 2273
(2020/03/04)
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- An Alternative Metal-Free Aerobic Oxidative Cross-Dehydrogenative Coupling of Sulfonyl Hydrazides with Secondary Phosphine Oxides
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An alternative metal-free, efficient and practical approach for the preparation of phosphinothioates is established via the aerobic oxidative cross-dehydrogenative coupling (CDC) of sulfonyl hydrazides with secondary phosphine oxides catalyzed by tetrabutylammonium iodide (TBAI) in the presence of atmospheric oxygen. The strategy provides an array of diverse phosphinothioates in good to excellent yields. Furthermore, two representative bioactive molecules are synthesized on up to gram scale by utilizing this method.
- Cheng, Feixiang,Liu, Jianjun,Liu, Teng,Yu, Rong,Zhang, Yanqiong
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p. 253 - 262
(2019/12/28)
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- Structure-based design, synthesis, and evaluation of the biological activity of novel phosphoroorganic small molecule IAP antagonists
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One of the strategies employed by novel anticancer therapies is to put the process of apoptosis back on track by blocking the interaction between inhibitor of apoptosis proteins (IAPs) and caspases. The activity of caspases is modulated by the caspases themselves in a caspase/procaspase proteolytic cascade and by their interaction with IAPs. Caspases can be released from the inhibitory influence of IAPs by proapoptotic proteins such as secondary mitochondrial activator of caspases (Smac) that share an IAP binding motif (IBM). The main purpose of the present study was the design and synthesis of phosphorus-based peptidyl antagonists of IAPs that mimic the endogenous Smac protein, which blocks the interaction between IAPs and caspases. Based on the structure of the IAP antagonist and recently reported thiadiazole derivatives, we designed and evaluated the biochemical properties of a series of phosphonic peptides bearing the N-Me-Ala-Val/Chg-Pro-OH motif (Chg: cyclohexylglycine). The ability of the obtained compounds to interact with the binding groove of the X-linked inhibitor of apoptosis protein baculovirus inhibitor of apoptosis protein repeat (XIAP BIR3) domain was examined by a fluorescence polarization assay, while their potential to induce autoubiquitination followed by proteasomal degradation of cellular IAP1 was examined using the MDA-MB-231 breast cancer cell line. The highest potency against BIR3 was observed among peptides containing C-terminal phosphonic phenylalanine analogs, which displayed nanomolar Ki values. Their antiproliferative potential as well as their proapoptotic action, manifested by an increase in caspase-3 activity, was examined using various cell lines.
- ?upicka-S?owik, Agnieszka,Psurski, Mateusz,Grzywa, Renata,Cuprych, Monika,Ciekot, Jaros?aw,Goldeman, Waldemar,Wojaczyńska, El?bieta,Wojaczyński, Jacek,Oleksyszyn, Józef,Sieńczyk, Marcin
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p. 1350 - 1364
(2020/04/24)
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- METHODS FOR PREPARING BIS-TETRAHYDROISOQUINOLINE-CONTAINING COMPOUNDS
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(-)-Jorumycin, ecteinascidin 743, saframycin A and related compounds, methods of preparing the same, formulations comprising the compounds, and methods of treating proliferative diseases with the same are provided.
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Page/Page column 91
(2019/02/06)
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- Palladium-Catalyzed C-P Cross-Coupling between (Het)aryl Halides and Secondary Phosphine Oxides
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An efficient procedure for C-P bond formation via the palladium-catalyzed [Pd(OAc) 2 /dppf/Cs 2 CO 3 ] reaction between dichloroheterocycles and secondary phosphine oxides was developed. The steric and electronic properties of substituents were varied to establish the scope and limitations of the method developed. By applying these conditions, a variety of new heterocyclic compounds bearing two tertiary phosphine oxides were successfully synthesized in moderate to excellent yields. After adjustments to the reaction conditions [Pd(OAc) 2 /dippf/ t -BuOK], cross-coupling of secondary phosphine oxides with bulky (secondary or tertiary alkyl) substituents on the phosphorus atom was achieved. Extension of the methodology to monohalohetarenes and monohaloarenes was successfully carried out; once again, the steric and electronic properties of the halides were varied widely. The desired reaction occurred in all cases studied, giving high to excellent yields of product regardless of the nature and positions of substituents.
- Zakirova, Gladis G.,Mladentsev, Dmitrii Yu.,Borisova, Nataliya E.
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p. 2379 - 2386
(2019/05/24)
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- Highly chemo- and regioselective C-P cross-coupling reaction of quinone imine ketals with Ar2P(O)H to construct: Ortho -amino triarylphosphine derivatives
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A highly chemo- and regioselective approach for the construction of ortho-amino triarylphosphine oxides has been achieved through a C-P cross-coupling reaction involving quinone imine ketals (QIKs) with Ar2P(O)H and catalyzed via a Lewis base. This alternative protocol provided a wide substrate scope with excellent yields (82-95%), and a variety of ortho-amino triarylphosphines were obtained with high yields (87-95%) via further reductive reaction. Furthermore, this reaction could be scaled-up and several synthetic transformations were accomplished for the construction of functionalized organophosphorus.
- Liu, Teng,Li, Yongqin,Cheng, Feixiang,Shen, Xianfu,Liu, Jianjun,Lin, Jun
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supporting information
p. 3536 - 3541
(2019/07/10)
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- Cobaloxime Catalysis: selective synthesis of alkenylphosphine oxides under visible light
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Direct activation of H-phosphine oxide to react with an unsaturated carbon-carbon bond is a straightforward approach for accessing alkenylphosphine oxides, which shows significant applications in both synthetic and material fields. However, expensive metals and strong oxidants are typically required to realize the transformation. Here, we demonstrate the utility of earth-abundant cobaloxime to convert H-phosphine oxide into its reactive radical species under visible light irradiation. The radical species thus generated can be utilized to functionalize alkenes and alkynes without any external photosensitizer and oxidant. The coupling with terminal alkene generates E-alkenylphosphine oxide with excellent chemo- A nd stereoselectivity. The reaction with terminal alkyne yields linear E-alkenylphosphine oxide via neutral radical addition, while addition with internal ones generates cyclic benzophosphine oxides and hydrogen. Mechanistic studies on radical trapping experiments, electron spin resonance studies, and spectroscopic measurements confirm the formation of phosphinoyl radical and cobalt intermediates that are from capturing the electron and proton eliminated from H-phosphine oxide. The highlight of our mechanistic investigation is the dual role played by cobaloxime, viz., both as the visible light absorber to activate the P(O)-H bond as well as a hydrogen transfer agent to influence the reaction pathway. This synergetic feature of the cobaloxime catalyst preforming multiple functions under ambient condition provides a convergent synthetic approach to vinylphosphine oxides directly from H-phosphine oxides and alkenes (or alkynes).
- Liu, Wen-Qiang,Lei, Tao,Zhou, Shuai,Yang, Xiu-Long,Li, Jian,Chen, Bin,Sivaguru, Jayaraman,Tung, Chen-Ho,Wu, Li-Zhu
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supporting information
p. 13941 - 13947
(2019/09/30)
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- Cobaloxime Catalysis: Selective Synthesis of Alkenylphosphine Oxides under Visible Light
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Direct activation of H-phosphine oxide to react with an unsaturated carbon-carbon bond is a straightforward approach for accessing alkenylphosphine oxides, which shows significant applications in both synthetic and material fields. However, expensive metals and strong oxidants are typically required to realize the transformation. Here, we demonstrate the utility of earth-abundant cobaloxime to convert H-phosphine oxide into its reactive radical species under visible light irradiation. The radical species thus generated can be utilized to functionalize alkenes and alkynes without any external photosensitizer and oxidant. The coupling with terminal alkene generates E-alkenylphosphine oxide with excellent chemo- and stereoselectivity. The reaction with terminal alkyne yields linear E-alkenylphosphine oxide via neutral radical addition, while addition with internal ones generates cyclic benzophosphine oxides and hydrogen. Mechanistic studies on radical trapping experiments, electron spin resonance studies, and spectroscopic measurements confirm the formation of phosphinoyl radical and cobalt intermediates that are from capturing the electron and proton eliminated from H-phosphine oxide. The highlight of our mechanistic investigation is the dual role played by cobaloxime, viz., both as the visible light absorber to activate the P(O)-H bond as well as a hydrogen transfer agent to influence the reaction pathway. This synergetic feature of the cobaloxime catalyst preforming multiple functions under ambient condition provides a convergent synthetic approach to vinylphosphine oxides directly from H-phosphine oxides and alkenes (or alkynes).
- Liu, Wen-Qiang,Lei, Tao,Zhou, Shuai,Yang, Xiu-Long,Li, Jian,Chen, Bin,Sivaguru, Jayaraman,Tung, Chen-Ho,Wu, Li-Zhu
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supporting information
p. 13941 - 13947
(2019/09/30)
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- Iodine phosphine oxide ligand, preparation method and complex thereof, catalyst system comprising complex and application
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The invention relates to an iodine phosphine oxide ligand, a preparation method and a complex thereof, a catalyst system comprising the complex, a method for preparing isooctanoic acid from 2-ethylhexanal by oxidizing in the presence of the catalyst system and an application of the catalyst system. In the catalyst system, isooctanoic acid is prepared from 2-ethylhexanal by oxidizing on the basis of the iodine phosphine oxide ligand and a cesium complex taken as catalysts and potassium salt taken as a catalyst aid. The defect of poor selectivity in the prior art can be overcome, the process ismild, and the ligand is convenient to prepare and has high activity and small dosage.
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Paragraph 0071-0073
(2019/01/23)
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- Preparation of organophosphorus compounds from P-H compounds using o-(trimethylsilyl)aryl triflates as aryne precursors
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An efficient method was developed for the synthesis of a variety of arylphosphorus compounds from P-H compounds using o-(trimethylsilyl)aryl triflates as aryne precursors. The reaction provides a practical preparation of various arylphosphorus compounds via aryne intermediates utilizing diarylphosphine oxides and dialkyl phosphites as the nucleophiles.
- Yang, Guoqiang,Shen, Chaoren,Quan, Mao,Zhang, Wanbin
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supporting information
p. 333 - 337
(2015/12/30)
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- Synthesis and Characterization of Manganese(I) Carbonyl Complexes of the Type [(OC)4Mn{μ-P(R)Aryl}]2
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Metalation of secondary phosphanes HPRR′ [R = R′ = C6H4-4-Me, C6H3-3,5-Me2 (3), C6H4-4-NMe2 (4); R/R′ = Ph/cHex] with Mn2(CO)10 in boiling xylene
- Mede, Ralf,Blohm, Sascha,G?rls, Helmar,Westerhausen, Matthias
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supporting information
p. 508 - 514
(2016/04/19)
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- SPIRO-1,1'-BIINDANE-7,7-BISPHOSPHINE OXIDES AS HIGHLY ACTIVE SUPPORTING LIGANDS FOR PALLADIUM-CATALYZED ASYMMETRIC HECK REACTION
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The present invention relates to catalyst complexes comprising palladium (Pd) and at least one spiro-1,1 '-biindane-7,7'- bisphosphine oxide ligand as disclosed herein, and their use. The present invention is further directed to the asymmetric Pd-catalyzed covalent carbon-carbon single bond formation from aryl, heteroaryl and alkenyl triflates and halides and olefins utilising the said catalyst complexes.
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Page/Page column 21; 22
(2015/01/06)
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- Chiral magnesium(II) binaphtholates as cooperative bronsted/lewis acid-base catalysts for the highly enantioselective addition of phosphorus nucleophiles to α,β-unsaturated esters and ketones
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A little cooperation goes a long way: The cooperative Bronsted/Lewis acid-base supramolecular catalysts formed in situ from simple chiral magnesium(II) binaphtholate aqua complexes promoted the highly enantioselective 1,4-hydrophosphinylation of α,β-unsaturated esters with diaryl phosphine oxides and 1,2-hydrophosphonylation of α,β-unsaturated ketones with dialkyl phosphites (see scheme). Copyright
- Hatano, Manabu,Horibe, Takahiro,Ishihara, Kazuaki
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supporting information
p. 4549 - 4553
(2013/06/04)
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- Highly active catalysts of bisphosphine oxides for asymmetric Heck reaction
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Bisphosphine oxides formed highly active asymmetric Heck catalysts, which were applied in asymmetric synthesis of pharmacologically active azacycles. Olefin insertion proceeded via cis pathways, different from P,N-ligands.
- Hu, Jian,Lu, Yunpeng,Li, Yongxin,Zhou, Jianrong
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supporting information
p. 9425 - 9427
(2013/10/01)
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- Ruthenium-catalyzed regio- and enantioselective allylic substitution with water: Direct synthesis of chiral allylic alcohols
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Less is more: A new route to access chiral allylic alcohols through the regio- and enantioselective substitution of monosubstituted allylic chlorides with water has been developed. The reaction is catalyzed effectively by planar-chiral cyclopentadienyl ruthenium complexes (see scheme). Copyright
- Kanbayashi, Naoya,Onitsuka, Kiyotaka
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supporting information; experimental part
p. 5197 - 5199
(2011/06/26)
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- Process research on the asymmetric hydrogenation of a benzophenone for developing the manufacturing process of the squalene synthase inhibitor TAK-475
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A practical synthetic method for the synthesis of the chiral benzhydrol 8, which is the key intermediate of the squalene synthase inhibitor TAK-475 (1), has been developed. The method, via asymmetric hydrogenation of the benzophenone 7, employed Noyori's ruthenium precatalyst of the type [RuCl 2(diphosphine)(diamine). We focused on tuning of the chiral diphosphine, and have discovered a novel ligand, DADMP-BINAP (18c), for the catalyst that has allowed reduction of the operating pressure in the asymmetric hydrogenation. The precatalyst containing 18c performed effectively at low hydrogen pressure (1 MPa) with sufficient enantioselectivity, and the result enabled us to successfully obtain enantiomerically pure 8 on a multikilogram scale.
- Goto, Mitsutaka,Konishi, Takahiro,Kawaguchi, Shinji,Yamada, Masatoshi,Nagata, Toshiaki,Yamano, Mitsuhisa
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scheme or table
p. 1178 - 1184
(2011/12/16)
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- PROCESS FOR PREPARATION OF DIPHOSPHINE COMPOUNDS AND INTERMEDIATES FOR THE PROCESS
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A production method of a_compound represented by the formula wherein R1a, R1b, R1c, R1d, R1e, R1f, R2a, R2b, R2c R2d, R2e and R2f are the same or different and each is a hydrogen atom and the like, and R3, R4, R5, R6, R7, R8, R9 and R10 are the same or different and each is a hydrogen atom and the like, or a salt thereof, which comprises reacting a compound represented by the formula wherein X is a leaving group and other symbols are as defined above, or a salt thereof, with a phosphine-borane complex represented by the formula wherein the symbols are as defined above, or a salt thereof, in a solvent in the presence of an amine and a nickel catalyst, is provided.
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- General synthetic route to chiral flexible biphenylphosphine ligands: The use of a chiral additive enables the preparation and observation of metal complexes incorporating the enantiopure form
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equation presented The enantio-and diastereomerically pure metal complex of a chirally flexible BIPHEP ligand is obtained through enantiomer-selective coordination of a BIPHEP-Ru complex with enantiopure 3,3′-dimethyldiaminobinaphthyl, DM-DBN, followed by
- Mikami, Koichi,Aikawa, Kohsuke,Korenaga, Toshinobu
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p. 243 - 245
(2007/10/03)
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- Phospphine-phosinite compound and process for preparing 4-?(R)-1'-formylethyl!-azetidin-2-one derivatives using the same
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A phosphine-phosphinite compound represented by formula (I): STR1 wherein R1 and R2, which may be the same or different, each represent a substituted or unsubstituted phenyl group or a substituted or unsubstituted naphthyl group, and
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- Ligand Electronic Effects in Asymmetric Catalysis: Enhanced Enantioselectivity in the Asymmetric Hydrocyanation of Vinylarenes
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The enantioselectivity of the nickel-catalyzed, asymmetric hydrocyanation of vinylarenes using glucosederived, chiral phosphinite ligands, L, increases dramatically when the ligands contain electron-withdrawing P-aryl substituents.The substrate and solvent also strongly influence the enantioselectivity, with the highest ee's (85-91percent for 6-methoxy-2-vinylnaphthalene (MVN)) obtained for the hydrocyanation of electron-rich vinylarenes in a nonpolar solvent such as hexane.Mechanistic studies suggest the catalytic cycle consists of an initial HCN oxidative addition or vinylarene coordination to "NiL", followed by insertion to form an (η3-benzyl)nickel cyanide complex, and irreversible reductive elimination of the nitrile.A kinetic analysis of the NiLa(COD) (La, P-aryl=3,5-(CF3)2C6H3) catalyzed hydrocyanation of MVN indicates that as the HCN concentration is increased the catalyst resting state shifts from NiLa(COD) to a complex containing both MVN and HCN, presumably the (η3-benzyl)nickel cyanide intermediate NiLa(η3-CH3CHC10H6OCH3)CN.A 31P NMR analysis of the intermediate NiLa(MVN) shows little ground state differentiation of the MVN enantiofaces and suggests that the enantioselectivity is determined later in the mechanism.Deuterium labeling studies suggest that electron-withdrawing P-aryl substituents increase the rate of reductive elimination of the product nitrile from the (η3-benzyl)nickel cyanide intermediate and, on this basis, a rationale for the ligand electronic effect is proposed.
- Casalnuovo, Albert L.,RajanBabu, T. V.,Ayers, Timothy A.,Warren, Timothy H.
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p. 9869 - 9882
(2007/10/02)
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