Article
Chemistry, Multidisciplinary
Titouan Desrues, Jeremy Merad, Daniela Andrei, Jean-Marc Pons, Jean-Luc Parrain, Maurice Medebielle, Adrien Quintard, Cyril Bressy
Summary: This study reported an enantioselective organocatalyzed acylation of alpha,alpha-difluorohydrins using a commercially available chiral isothiourea, greatly improving the enantioselectivity of the kinetic resolution process through electrostatic fluorine-cation interactions. The method allows for the synthesis of various fluorinated alcohols with exquisite enantiocontrol, such as 4,4-difluoro-1,3-diols, as well as demonstrated compatibility between aromatic and fluorinated groups in providing enantioenriched adducts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Yongkai Pan, Qianwen Jiang, Subramani Rajkumar, Chaofan Zhu, Jinglei Xie, Shaoze Yu, Yunrong Chen, Yu-Peng He, Xiaoyu Yang
Summary: A series of cyclohexyl-fused SPINOL-derived phosphoric acids have been developed for the kinetic resolution of 2-N-acylamido tertiary allylic alcohols, providing access to chiral oxazolines with high enantioselectivities. Gram-scale reactions with 1 mol% catalyst loading and transformations of the chiral products demonstrate the value of these methods.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Review
Chemistry, Organic
Bo Ding, Qilin Xue, Shihu Jia, Hong-Gang Cheng, Qianghui Zhou
Summary: This review provides an overview of recent advances in catalytic nonenzymatic kinetic resolution (KR) of tertiary alcohols, including organocatalysis and metal catalysis.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Organic
Xueyang Liu, Jean-Marc Pons, Valerie Monnier, Laurence Charles, Adrien Quintard, Cyril Bressy
Summary: This paper describes an efficient enantioselective kinetic resolution method for the separation of secondary alcohols with a quaternary stereocenter. It utilizes a commercially available chiral isothiourea organocatalyst and achieves high levels of stereoselectivity in a wide range.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Valluru Krishna Reddy, Keizo Kan, Yasser Samir Abdel-Khalek Sokeirik, Keisuke Yoshida, Atsushi Hirata, Masahiro Yamanaka, Yoshihiro Ueda, Takeo Kawabata
Summary: The method for kinetic resolution of 2,2'-disubstituted 1,1'-binaphthyl-8,8'-diamines was developed through enantioselective acylation of the amino group with chiral pyrrolidinopyridine organocatalysts. The accelerative enantioselective acylation was proposed to be due to multiple hydrogen-bonding interactions and pi-pi interaction between the catalyst and the diamines.
Article
Chemistry, Multidisciplinary
Mengyao Tang, Huanchao Gu, Shunlong He, Subramani Rajkumar, Xiaoyu Yang
Summary: An efficient protocol for kinetic resolution of tertiary alcohols has been developed via unprecedented asymmetric enamide-imine tautomerism process enabled by chiral phosphoric acid catalysis. This method is particularly effective for a series of 1,1-dialkyl substituted allyl alcohols, producing chiral tertiary alcohols that are difficult to access through other asymmetric methods. Facile and versatile transformations of the chiral products demonstrate the value of this kinetic resolution method.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Jian Song, Wen-Hua Zheng
Summary: A highly enantioselective method for the kinetic resolution of racemic tertiary alcohols has been developed using chiral organotin-catalyzed intermolecular acylation. The process can be carried out under mild reaction conditions and has a broad substrate scope, allowing for the separation of the corresponding products and highly enantioselective recovery of tertiary alcohols with s factors up to >200.
Article
Chemistry, Organic
Ken-ichi Yamada, Akiho Yamauchi, Tatsuya Fujiwara, Keiji Hashimoto, Yinli Wang, Satoru Kuwano, Tsubasa Inokuma
Summary: The effect of N-substituent on the performance of chiral N-heterocyclic carbene-catalyzed kinetic resolution using alpha-hydroxyamides was investigated. N-tert-Butyl-alpha-hydroxyamides exhibited the best performance and achieved enantioselective acylation with alpha-bromo aldehyde through chiral N-heterocyclic carbene/carboxylate anion co-catalysis, leading to a high selectivity factor up to 128.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Donghui Guo, Qiupeng Peng, Bei Zhang, Jian Wang
Summary: The novel method described in this report allows for the atroposelective generation of axially chiral amino esters using hemiaminals formed in situ, with a wide substrate scope, good functional group tolerance, and rapid assembly of axially chiral amino esters with high enantioselectivities in good to high yields.
Article
Chemistry, Multidisciplinary
Qianwen Jiang, Wansen Xie, Xiaoyu Yang
Summary: The asymmetric synthesis of highly sterically congested alpha-tertiary amines was achieved by an organocatalyzed kinetic resolution (KR) protocol, which were otherwise difficult to access. A variety of substituted N-aryl alpha-tertiary amines bearing 2-substitued phenyl groups were kinetically resolved through the asymmetric C-H amination reaction, affording good to high KR performances.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Kui Liao, Yi Gong, Ren-Yi Zhu, Cai Wang, Feng Zhou, Jian Zhou
Summary: This study reports the first highly enantioselective Cu-I-catalyzed azide-alkyne cycloaddition of tertiary alcohols and their kinetic resolution, with newly developed PYBOX ligands playing a key role in achieving facile access to multifunctional tertiary alcohols. This approach represents the first successful kinetic resolution of racemates with a tetrasubstituted carbon stereocenter via CuAAC.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Guanghui Wang, Lulu Li, Yifeng Jiang, Xiaowei Zhao, Xu Ban, Tianju Shao, Yanli Yin, Zhiyong Jiang
Summary: A chiral Bronsted acid catalysed phosphine-mediated deoxygenation protocol has been reported for the synthesis of azaarylethynyl tertiary alcohols and azaaryl-functionalized allenes, which are biologically and synthetically important derivatives. This metal-free method demonstrates high efficiency, excellent enantioselectivities, broad substrate scope, and practicality for the synthesis of deuterated allenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Organic
Chen Yunrong, Liu Wei, Yang Xiaoyu
Summary: Chiral tertiary alcohols play important roles in various bioactive compounds, and significant progress has been made in the nonenzymatic kinetic resolution of tertiary alcohols in recent years, exploring the application of novel asymmetric reactions and catalytic systems.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Hiroki Mandai, Ryuhei Shiomoto, Kazuki Fujii, Koichi Mitsudo, Seiji Suga
Summary: An efficient acylative kinetic resolution method for 3-hydroxy-3-substituted 2-oxindoles has been developed using a chiral DMAP derivative. The catalyst showed high efficiency with a wide range of substrates and could achieve high resolution within a short reaction time.
Article
Chemistry, Organic
Samuel M. Smith, Mark D. Greenhalgh, Taisiia Feoktistova, Daniel M. Walden, James E. Taylor, David B. Cordes, Alexandra M. Z. Slawin, Paul Ha-Yeon Cheong, Andrew D. Smith
Summary: This study reports the full scope and limitations of catalytic acylative kinetic resolution of a range of tertiary heterocyclic alcohols using a commercially available Lewis basic isothiourea catalyst. The protocol is highly effective for the synthesis of enantioenriched compounds and a detailed kinetic analysis of the reaction mechanism has been provided.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Callum Prentice, James Morrison, Andrew D. Smith, Eli Zysman-Colman
Summary: The donor-acceptor thermally activated delayed fluorescent compounds DiKTa and Mes(3)DiKTa were found to have comparable or better product yields than 4CzIPN in a range of photocatalytic reactions. Among them, DiKTa stands out due to its lower cost, making it a valuable addition to any chemist's collection of photocatalysts.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Subeesh Madayanad Suresh, Le Zhang, David Hall, Changfeng Si, Gaetano Ricci, Tomas Matulaitis, Alexandra M. Z. Slawin, Stuart Warriner, Yoann Olivier, Ifor D. W. Samuel, Eli Zysman-Colman
Summary: NOBNacene is a rare example of a p- and n-doped nonacene compound with linearly extended ladder-type multiresonant thermally activated delayed fluorescence (MR-TADF) emission. It exhibits efficient narrow deep blue emission with a PL wavelength of 410 nm, FWHM of 38 nm, PL quantum yield of 71%, and delayed lifetime of 1.18 ms. The OLED using NOBNacene as the emitter shows a comparable electroluminescence spectrum with a peak at 409 nm and a maximum external quantum efficiency (EQE(max)) of 8.5% at CIE coordinates of (0.173, 0.055). The EQE(max) is increased to 11.2% with 3 wt% doping of the emitter in the emissive layer, resulting in a slightly broadened electroluminescence spectrum with CIE coordinates of (0.176, 0.068).
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Eimantas Duda, Subeesh Madayanad Suresh, David Hall, Sergey Bagnich, Rishabh Saxena, David B. Cordes, Alexandra M. Z. Slawin, David Beljonne, Yoann Olivier, Anna Koehler, Eli Zysman-Colman
Summary: This study introduces a molecular design that gradually increases the number of quasi-degenerate states to enhance the efficiency of thermally activated delayed fluorescence (TADF) using the oligomer approach. By selecting and arranging benzonitrile (BN) acceptors and amine donors, connected together via repetitive donor-acceptor units, the number of quasi-degenerate states is gradually increased. It is found that increasing the size of the oligomer enhances the rates of intersystem crossing and reverse intersystem crossing.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Organic
Yihong Wang, Claire M. M. Young, David B. B. Cordes, Alexandra M. Z. Slawin, Andrew D. D. Smith
Summary: The isothiourea-catalyzed formal [2+ 2] cycloaddition of C(1)-alkyl and C(1)-unsubstituted ammonium enolates with beta- and alpha,beta-substituted trifluoromethylenones has been developed. The reaction exhibited preferential [2 + 2]-cycloaddition over the alternative [4 + 2]-cycloaddition, resulting in beta-lactones with excellent diastereo- and enantioselectivity. The regioselectivity of the reaction was determined by the substituents on both reactants.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
R. Alan Aitken, Lynn A. A. Power, Alexandra M. Z. Slawin
Summary: (2S,5S)-5-Phenyl-2-t-butyl-1,3-dioxolan-4-one, derived from mandelic acid, can undergo Michael addition reactions with butenolide and 4-methoxy-beta-nitrostyrene, with the absolute configuration of the products confirmed by X-ray diffraction. Thermal fragmentation of the dioxolanone in these reactions results in the formation of phenyl ketone and chiral epoxy ketone, demonstrating its role as a chiral benzoyl anion equivalent and chiral ketene equivalent, respectively. Additionally, the Diels-Alder cycloaddition chemistry of (2S)-5-methylene-2-t-butyl-1,3-dioxolan-4-one, derived from lactic acid, has been studied, and the X-ray structures of four adducts have been determined, providing insights into the mechanism of dioxolanone fragmentation.
Article
Chemistry, Organic
Jan U. Bergsch, Alexandra M. Z. Slawin, Petr Kilian, Brian A. Chalmers
Summary: Researchers successfully synthesized two new types of Sb(III) and Sb(V) peri-substituted acenaphthene phosphorus-antimony compounds. The Sb(III) compound, 1, was prepared by reacting the organolithium precursor with dichloro(p-tolyl)stibine, and 2 was prepared by chlorination of 1. Both compounds were characterized by multinuclear (H-1, C-13, and P-31) NMR spectroscopy and their molecular structures were resolved by single-crystal X-ray diffraction. Both compounds exhibit a dative P-Sb interaction with antimony serving as the Lewis acidic acceptor group.
Article
Chemistry, Organic
Zachary H. Davis, Cameron L. Carpenter-Warren, Laurence J. Taylor, Alexandra M. Z. Slawin, Petr Kilian, Brian A. Chalmers
Summary: A binuclear tungsten(0) complex with an asymmetric bridging 1,2-diphosphole ligand was synthesized by the photolysis of tungsten hexacarbonyl in the presence of 1-isopropyl-2-phenyl-1,2,5,6-tetrahydroacenaphtho [5,6-cd][1,2]diphosphole. The tungsten complex 1 was characterized by high resolution mass spectrometry, multinuclear NMR spectroscopy (H-1, C-13, P-31), and elemental microanalysis. The structure of the trans isomer was resolved by single crystal X-ray diffraction, showing a slight elongation of the P-P bond upon coordination to the W(CO)(5) groups.
Article
Chemistry, Inorganic & Nuclear
Lutao Zhang, Francesca A. Christie, Anna E. Tarcza, Helena G. Lancaster, Laurence J. Taylor, Michael Buhl, Olga L. Malkina, J. Derek Woollins, Cameron L. Carpenter-Warren, David B. Cordes, Alexandra M. Z. Slawin, Brian A. Chalmers, Petr Kilian
Summary: A series of peri-substituted acenaphthene-based phosphine selenoether bidentate ligands were synthesized and their properties in coordination with metals were investigated. The rigid ligands exhibited strong coupling effects and the coordination atoms were bridged by Lewis acidic motifs in the solid-state structures. Analysis of the NMR and X-ray diffraction data of the synthesized metal complexes provided insights into the interaction between the ligands and metals.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Stuart Burnett, Rochelle Ferns, David B. Cordes, Alexandra M. Z. Slawin, Tanja van Mourik, Andreas Stasch
Summary: This article reports on the different complexes obtained from the reactions of [(iPrDip)NacNac)Mg}(2)] with different reactants and reveals the structural characteristics of these complexes through experimental and computational studies.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
R. Alan Aitken, Lynn A. Power, Alexandra M. Z. Slawin
Summary: X-ray diffraction analysis confirmed that the product formed by base-induced dimerization matches the described compound structure, rather than the previously proposed isomeric structure. Additionally, a similar compound derived from a different substrate was obtained and characterized.
Article
Chemistry, Organic
R. Alan Aitken, Alexandra H. Campbell, Chloe E. Fletcher, Alexandra M. Z. Slawin
Article
Chemistry, Inorganic & Nuclear
Hessa H. Al-Rasheed, Sarah A. AL-khamis, Ayman El-Faham, Assem Barakat, Alexandra M. Z. Slawin, John Derek Woollins, Saied M. Soliman
Summary: The unexpected tetranuclear [Cu-4(DPPT)(2)Cl-6] complex was obtained through self-assembly, and it showed good antifungal and antibacterial activity against Gram-positive bacteria.
Article
Materials Science, Multidisciplinary
Dongyang Chen, Le Zhang, Tomas Matulaitis, David B. Cordes, Alexandra M. Z. Slawin, Xiao-Hong Zhang, Ifor D. W. Samuel, Eli Zysman-Colman
Summary: By judicious molecular engineering, the efficiency of the triplet exciton harvesting mechanisms in OLEDs can be modulated, leading to improved device efficiency.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Organic
Miguel A. Valle-Amores, Claudia Feberero, Ana Martin-Somer, Sergio Diaz-Tendero, Andrew D. Smith, Alberto Fraile, Jose Aleman
Summary: In this study, a highly enantioselective organocatalyzed [3 + 2] cycloaddition reaction between furanone derivatives and azomethine ylides was presented. The success of this reaction is attributed to intramolecular hydrogen bond activation and the formation of highly multifunctional bicyclic adducts with five stereogenic centers. The reaction also achieved a highly efficient kinetic resolution of butenolides, leading to the formation of furan-2(5H)-ones and furo[3,4-c]pyrrolidinones with high enantioselectivities. Quantum chemistry calculations revealed the crucial role of hydrogen bonding in promoting facial discrimination and achieving a highly selective kinetic resolution.
ORGANIC CHEMISTRY FRONTIERS
(2023)
