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1.
Design,Synthesis, and Application of Chiral C2‐Symmetric Spiroketal‐Containing Ligands in Transition‐Metal Catalysis
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Alonso J. Argüelles Siyuan Sun Brenna G. Budaitis Prof. Dr. Pavel Nagorny 《Angewandte Chemie (International ed. in English)》2018,57(19):5325-5329
We present an expedient and economical route to a new spiroketal‐based C2‐symmetric chiral scaffold, termed SPIROL. Based on this spirocyclic scaffold, several chiral ligands were generated. These ligands were successfully employed in an array of stereoselective transformations, including in iridium‐catalyzed hydroarylations (up to 95 % ee), palladium‐catalyzed allylic alkylations (up to 97 % ee), intermolecular palladium‐catalyzed Heck couplings (up to 94 % ee), and rhodium‐catalyzed dehydroalanine hydrogenation (up to 93 % ee). 相似文献
2.
Chiral Palladacycle Catalysts Generated on a Single‐Handed Helical Polymer Skeleton for Asymmetric Arylative Ring Opening of 1,4‐Epoxy‐1,4‐dihydronaphthalene
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Dr. Takeshi Yamamoto Yuto Akai Prof. Dr. Michinori Suginome 《Angewandte Chemie (International ed. in English)》2014,53(47):12785-12788
Post‐polymerization C? H activation of poly(quinoxaline‐2,3‐diyl)‐based helically chiral phosphine ligands (PQXphos) with palladium(II) acetate afforded chiral phosphapalladacycles quantitatively. In situ generated palladacycles exhibited enantioselectivities up to 94 % ee in the palladium‐catalyzed asymmetric ring‐opening arylation of 1,4‐epoxy‐1,4‐dihydronaphthalenes with arylboronic acids. 相似文献
3.
Majority‐Rules‐Type Helical Poly(quinoxaline‐2,3‐diyl)s as Highly Efficient Chirality‐Amplification Systems for Asymmetric Catalysis
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Dr. Tetsuya Yamada Prof. Dr. Michinori Suginome 《Angewandte Chemie (International ed. in English)》2015,54(32):9333-9337
A highly efficient majority‐rules effect of poly(quinoxaline‐2,3‐diyl)s (PQXs) bearing 2‐butoxymethyl chiral side chains at the 6‐ and 7‐positions was established and attributed to large ΔGh values (0.22–0.41 kJ mol?1), which are defined as the energy difference between P‐ and M‐helical conformations per chiral unit. A PQX copolymer prepared from a monomer derived from (R)‐2‐octanol (23 % ee) and a monomer bearing a PPh2 group adopted a single‐handed helical structure (>99 %) and could be used as a highly enantioselective chiral ligand in palladium‐catalyzed asymmetric reactions (products formed with up to 94 % ee), in which the enantioselectivity could be switched by solvent‐dependent inversion of the helical PQX backbone. 相似文献
4.
New chiral N,S-ligands with oxazoline and thiophenyl sub-stituents at benzene ring and benzylic postition have been pre-pared and applied in palladium-catalyzed asymmetric allylic alkylation reaction to provide the product with high yield and entantioselectivity (82%-93%)ee. 相似文献
5.
《中国化学》2018,36(2):153-156
A series of structurally novel P‐chiral biaryl bisphosphorus ligands L1‐L5 (BABIBOPs) are developed, providing high efficiency for the first time in palladium‐catalyzed asymmetric hydrogenation of β‐aryl and β‐alkyl substituted β‐keto esters. With the Pd‐ L3 (iPr‐BABIBOP) catalyst, a series of chiral β‐hydroxyl carboxylic esters are formed in excellent enantioselectivities (up to>99% ee) and yields at catalyst loading as low as 0.01 mol%. 相似文献
6.
Rhodium‐catalyzed Asymmetric Hydrogenation of α‐Dehydroamino Ketones: A General Approach to Chiral α‐amino Ketones
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Rhodium/DuanPhos‐catalyzed asymmetric hydrogenation of aliphatic α‐dehydroamino ketones has been achieved and afforded chiral α‐amino ketones in high yields and excellent enantioselectives (up to 99 % ee), which could be reduced further to chiral β‐amino alcohols by LiAlH(tBuO)3 with good yields. This protocol provides a readily accessible route for the synthesis of chiral α‐amino ketones and chiral β‐amino alcohols. 相似文献
7.
Scalable,Stereocontrolled Formal Syntheses of (+)‐Isoschizandrin and (+)‐Steganone: Development and Applications of Palladium(II)‐Catalyzed Atroposelective C−H Alkynylation
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Gang Liao Qi‐Jun Yao Zhuo‐Zhuo Zhang Yong‐Jie Wu Dan‐Ying Huang Prof. Dr. Bing‐Feng Shi 《Angewandte Chemie (International ed. in English)》2018,57(14):3661-3665
Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. Herein, we describe the development of a palladium‐catalyzed atroposelective C?H alkynylation and its application in gram‐scale, stereocontrolled formal syntheses of (+)‐isoschizandrin and (+)‐steganone. tert‐Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 % ee). 相似文献
8.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(14):3723-3727
Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. Herein, we describe the development of a palladium‐catalyzed atroposelective C−H alkynylation and its application in gram‐scale, stereocontrolled formal syntheses of (+)‐isoschizandrin and (+)‐steganone. tert‐Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 % ee). 相似文献
9.
Yang‐Zi Liu Zhongao Wang Zesheng Huang Xing Zheng Wu‐Lin Yang Wei‐Ping Deng 《Angewandte Chemie (International ed. in English)》2020,59(3):1238-1242
The palladium‐catalyzed asymmetric [4+3] cyclization of trimethylenemethane donors with benzofuran‐derived azadienes furnishes chiral benzofuro[3,2‐b]azepine frameworks in high yields (up to 98 %) with exclusive regioselectivities and excellent stereoselectivities (up to >20:1 d.r., >99 % ee). This catalytic asymmetric [4+3] cyclization of Pd‐trimethylenemethane can enrich the arsenal of Pd‐TMM reactions in organic synthesis. In addition, this strategy provides an alternative approach to chiral azepines by a transition‐metal‐catalyzed asymmetric [4+3] cyclization. 相似文献
10.
IntroductionWiththefamousDIOPligand ,KaganintroducedtheimportantconceptofC2 symmetryinliganddesign .1However ,itisnotalwaystruethataC2 symmetricligandshouldnecessarilybesuperiortoanon symmetriccoun terpart .Transitionmetal catalyzedallylicalkylationviasymme… 相似文献
11.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(20):5955-5959
A facile access to optically active cyclic ureas was developed through palladium‐catalyzed asymmetric hydrogenation of pyrimidines containing tautomeric hydroxy group with up to 99 % ee. Mechanistic studies indicated that reaction pathway proceed through hydrogenation of C=N of the oxo tautomer pyrimidin‐2(1H)‐one, acid‐catalyzed isomerization of enamine–imine, and hydrogenation of imine pathway. In addition, the chiral cyclic ureas are readily converted into useful chiral 1,3‐diamine and thiourea derivatives without loss of optical purity. 相似文献
12.
Xiang Gao Bo Wu Wen‐Xue Huang Mu‐Wang Chen Yong‐Gui Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(41):12124-12128
A palladium‐catalyzed enantioselective C H functionalization of indoles was achieved with an axially chiral 2,2′‐bipyridine ligand, thus providing the desired indol‐3‐acetate derivatives with up to 98 % ee. Moreover, the reaction protocol was also effective for asymmetric O H insertion reaction of phenols using α‐aryl‐α‐diazoacetates. This represents the first successful application of bipyridine ligands with axial chirality in palladium‐catalyzed carbene migratory insertion reactions. 相似文献
13.
Biming Mao Honglei Liu Zhengyang Yan Yi Xu Jiaqing Xu Wei Wang Yongjun Wu Hongchao Guo 《Angewandte Chemie (International ed. in English)》2020,59(28):11316-11320
A palladium‐catalyzed asymmetric [4+2] cycloaddition of 2‐methylidenetrimethylene carbonate with alkenes derived from pyrazolones, indandione, or barbiturate has been successfully developed, affording pharmacologically interesting chiral tetrahydropyran‐fused spirocyclic scaffolds. The target compounds were generated in good to excellent yields and with high enantioselectivity (up to 99 % ee). Furthermore, this cycloaddition reaction could be efficiently scaled up, and several synthetic transformations were accomplished for the construction of other useful chiral spiropyrazolone and spiroindandione derivatives. 相似文献
14.
Xiang Gao Bo Wu Wen‐Xue Huang Mu‐Wang Chen Yong‐Gui Zhou 《Angewandte Chemie (International ed. in English)》2015,54(41):11956-11960
A palladium‐catalyzed enantioselective C H functionalization of indoles was achieved with an axially chiral 2,2′‐bipyridine ligand, thus providing the desired indol‐3‐acetate derivatives with up to 98 % ee. Moreover, the reaction protocol was also effective for asymmetric O H insertion reaction of phenols using α‐aryl‐α‐diazoacetates. This represents the first successful application of bipyridine ligands with axial chirality in palladium‐catalyzed carbene migratory insertion reactions. 相似文献
15.
Enantioselective Synthesis of Chiral Isotopomers of 1‐Alkanols by a ZACA–Cu‐Catalyzed Cross‐Coupling Protocol
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Dr. Shiqing Xu Akimichi Oda Prof. Dr. Ei‐ichi Negishi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(49):16060-16064
Chiral compounds arising from the replacement of hydrogen atoms by deuterium are very important in organic chemistry and biochemistry. Some of these chiral compounds have a non‐measurable specific rotation, owing to very small differences between the isotopomeric groups, and exhibit cryptochirality. This particular class of compounds is difficult to synthesize and characterize. Herein, we present a catalytic and highly enantioselective conversion of terminal alkenes to various β and more remote chiral isotopomers of 1‐alkanols, with ≥99 % enantiomeric excess (ee), by the Zr‐catalyzed asymmetric carboalumination of alkenes (ZACA) and Cu‐catalyzed cross‐coupling reactions. ZACA‐in situ iodinolysis of allyl alcohol and ZACA‐in situ oxidation of TBS‐protected ω‐alkene‐1‐ols protocols were applied to the synthesis of both (R)‐ and (S)‐difunctional intermediates with 80–90 % ee. These intermediates were readily purified to provide enantiomerically pure (≥99 % ee) compounds by lipase‐catalyzed acetylation. These functionally rich intermediates serve as very useful synthons for the construction of various chiral isotopomers of 1‐alkanols in excellent enantiomeric purity (≥99 % ee) by introducing deuterium‐labeled groups by Cu‐catalyzed cross‐coupling reactions without epimerization. 相似文献
16.
Xiaowei Zhang Bonan Cao Yongjun Yan Dr. Shichao Yu Dr. Baoming Ji Dr. Xumu Zhang Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(3):871-877
A series of hybrid phosphine–phosphoramidite ligands has been designed and synthesized in moderate yields from chiral BINOL (1,1′‐bi‐2‐naphthol) or NOBIN (2‐amino‐2′‐hydroxy‐1,1′‐binaphthyl). They have achieved highly regio‐ and enantioselectivities in Rh‐catalyzed asymmetric hydroformylations of styrene derivatives (branched/linear ratio up to 56.6, ee up to 99 %), vinyl acetate derivatives (up to 98 % ee), and allyl cyanide (up to 96 % ee). Systematic variation of ligand structure showed that the steric factor on the phsophoramidite moiety determined the performance of the ligand. With the increased hindrance, the branched/linear ratio rose, while the ee value dropped in the hydroformylation of styrene. However, the N‐substituents did not influence the selectivities much. 相似文献
17.
Stephan Enthaler Dr. Giulia Erre Kathrin Junge Dr. Daniele Addis Renat Kadyrov Dr. Matthias Beller Prof. Dr. 《化学:亚洲杂志》2008,3(7):1104-1110
The rhodium‐catalyzed asymmetric hydrogenation of different enamides, in particular, dihydro‐β‐carboline derivates, was investigated in the presence of chiral phosphorus ligands. Enantioselectivities of up to 99 % ee were obtained after ligand screening and optimization of the reaction conditions. The scope and limitation of the catalysts were shown in the synthesis of optically active tetrahydro‐β‐carbolines and other benchmark N‐acyl‐1‐aryl ethylamines. 相似文献
18.
《中国化学》2018,36(9):851-856
A series of novel and easily accessed ferrocene‐based amino‐phosphine‐sulfonamide (f‐Amphamide) ligands have been developed and applied in Ir‐catalyzed asymmetric hydrogenation of aryl ketones, affording the corresponding chiral secondary alcohols with excellent results (up to >99% conversion, >99% ee and TON up to 200 000). DFT calculations suggest an activating model involving an alkali cation Li+. 相似文献
19.
Bei‐Bei Zhan Lei Wang Jun Luo Xu‐Feng Lin Bing‐Feng Shi 《Angewandte Chemie (International ed. in English)》2020,59(9):3568-3572
A simple and ubiquitously present group, free amine, is used as a directing group to synthesize axially chiral biaryl compounds by PdII‐catalyzed atroposelective C?H olefination. A broad range of axially chiral biaryl‐2‐amines can be obtained in good yields with high enantioselectivities (up to 97 % ee). Chiral spiro phosphoric acid (SPA) proved to be an efficient ligand and the loading could be reduced to 1 mol % without erosion of enantiocontrol in gram‐scale synthesis. The resulting axially chiral biaryl‐2‐amines also provide a platform for the synthesis of a set of chiral ligands. 相似文献
20.
Yi Ding Ye‐Qiang Han Le‐Song Wu Tao Zhou Qi‐Jun Yao Ya‐Lan Feng Ya Li Ke‐Xin Kong Bing‐Feng Shi 《Angewandte Chemie (International ed. in English)》2020,59(33):14060-14064
Herein, we describe an unprecedented cascade reaction to β‐stereogenic γ‐lactams involving Pd(II)‐catalyzed enantioselective aliphatic methylene C(sp3)?H alkenylation–aza‐Wacker cyclization through syn‐aminopalladation. Readily available 3,3′‐substituted BINOLs are used as chiral ligands, providing the corresponding γ‐lactams with broad scope and high enantioselectivities (up to 98 % ee). 相似文献