1
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Giovanardi G, Cattani S, Balestri D, Secchi A, Cera G. Iridium-Catalyzed C-H Borylations: Regioselective Functionalizations of Calix[4]arene Macrocycles. J Org Chem 2024; 89:8486-8499. [PMID: 38816966 DOI: 10.1021/acs.joc.4c00419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
We report iridium-catalyzed C-H borylations for the regioselective synthesis of distally disubstituted calix[4]arene macrocycles. The atom- and step-economical method led to a broad family of calix[4]arenes in good yields and functional group tolerance. The synthetic utility of the C-H borylation protocol was finally illustrated with several late-stage modifications for the synthesis of elaborate calix[4]arenes frameworks, otherwise challenging to achieve with commonly employed procedures.
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Affiliation(s)
- Gabriele Giovanardi
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Silvia Cattani
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Davide Balestri
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Andrea Secchi
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Gianpiero Cera
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
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2
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Wang C, Chen N, Yang Z, Xu J. Y(OTf) 3-Salazin-Catalyzed Asymmetric Aldol Condensation. Molecules 2024; 29:1963. [PMID: 38731454 PMCID: PMC11085936 DOI: 10.3390/molecules29091963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 04/21/2024] [Accepted: 04/22/2024] [Indexed: 05/13/2024] Open
Abstract
The chiral aziridine-containing vicinal iminophenol tridentate ligands (named salazins) are a class of readily prepared chiral ligands from enantiopure aziridines and salicylaldehydes. Their scandium and yttrium triflate complexes show excellent reactivity and enantioselectivities in the catalytic asymmetric aldol condensation of electron-deficient aromatic aldehydes and ketones, including acetone and cycloalkanones. The stereoselectivity is rationalized to the strong π-stacking interaction between aromatic aldehydes and the vicinal iminophenol group in the chiral ligands.
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Affiliation(s)
| | | | | | - Jiaxi Xu
- State Key Laboratory of Chemical Resource Engineering, Department of Organic Chemistry, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, China; (C.W.); (N.C.); (Z.Y.)
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3
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Wen G, Feng X, Lin L. Water-enabling strategies for asymmetric catalysis. Org Biomol Chem 2024; 22:2510-2522. [PMID: 38450421 DOI: 10.1039/d3ob02122j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
Water possesses unique advantages, including abundance, environmental friendliness and mild effects. Undoubtedly, it is an ideal solvent or reagent in chemical syntheses. Water also shows unique abilities in catalytic asymmetric synthesis. It can accelerate reaction rates, improve diastereo- or enantioselectivities, initiate reactions, diversify chemo, diastereo- or enantioselectivities through various effects (hydrophobic, hydrogen bonding, protonation). Several reviews have demonstrated the positive effects of water in asymmetric synthesis. In this review, we summarize water-enabling strategies in the last decade, and focus on advances which reveal how water affects a reaction.
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Affiliation(s)
- Gang Wen
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Lili Lin
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
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4
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Begum Z, Seki C, Okuyama Y, Kwon E, Uwai K, Tokiwa M, Tokiwa S, Takeshita M, Nakano H. New boro amino amide organocatalysts for asymmetric cross aldol reaction of ketones with carbonyl compounds. RSC Adv 2023; 13:888-894. [PMID: 36686933 PMCID: PMC9811241 DOI: 10.1039/d2ra06272k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 12/20/2022] [Indexed: 01/05/2023] Open
Abstract
Distinct types of new boron fused primary amino amide organocatalysts were designed and synthesized from commercially available amino acids. Their catalytic activities were investigated in asymmetric crossed aldol reaction of ketones with aromatic aldehydes to afford the corresponding chiral anti-aldol adducts with good chemical yields, moderate diastereoselectivity and good to excellent enantioselectivities (up to 94% yields, up to 90 : 10 dr, up to 94% ee).
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Affiliation(s)
- Zubeda Begum
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology27-1 Mizumoto-choMuroran 050-8585Japan
| | - Chigusa Seki
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology27-1 Mizumoto-choMuroran 050-8585Japan
| | - Yuko Okuyama
- Tohoku Medical and Pharmaceutical University4-4-1 Komatsushima, Aoba-KuSendai 981-8558Japan
| | - Eunsang Kwon
- Research and Analytical Center for Giant Molecules, Graduate School of Sciences, Tohoku University6-3 Aoba, Aramaki, Aoba-KuSendai 980-8578Japan
| | - Koji Uwai
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology27-1 Mizumoto-choMuroran 050-8585Japan
| | - Michio Tokiwa
- Tokiwakai Group62 Numajiri Tsuduri-Chou UchigoIwaki 973-8053Japan
| | - Suguru Tokiwa
- Tokiwakai Group62 Numajiri Tsuduri-Chou UchigoIwaki 973-8053Japan
| | | | - Hiroto Nakano
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology27-1 Mizumoto-choMuroran 050-8585Japan
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5
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Sachdeva G, Vaya D, Srivastava CM, Kumar A, Rawat V, Singh M, Verma M, Rawat P, Rao GK. Calix[n]arenes and its derivatives as organocatalysts. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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6
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Simões JB, Leite da Silva D, Fernandes SA, de Fátima Â. Calix[n]arenes in Action: Recent Applications in Organocatalysis. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | - Ângelo de Fátima
- Universidade Federal de Minas Gerais Departamento de Química Av. Pres. Antônio Carlos, 6627, Pampulha 31270-901 Belo Horizonte BRAZIL
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7
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Xiong S, Nanda Kishore M, Zhou W, He Q. Recent advances in selective recognition of fluoride with macrocyclic receptors. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214480] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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8
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Supramolecular interaction controlled and calix[4]arene ligand assisted Pd-catalyzed C(sp3)−H arylation of aliphatic aldehydes. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.03.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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9
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Thiyagarajan R, Begum Z, Seki C, Okuyama Y, Kwon E, Uwai K, Tokiwa M, Tokiwa S, Takeshita M, Nakano H. New small γ-turn type N-primary amino terminal tripeptide organocatalyst for solvent-free asymmetric aldol reaction of various ketones with aldehydes. RSC Adv 2021; 11:38925-38932. [PMID: 35493209 PMCID: PMC9044195 DOI: 10.1039/d1ra08635a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 11/30/2021] [Indexed: 01/18/2023] Open
Abstract
New small γ-turn type N-primary amino terminal tripeptides were synthesized and their functionality as an organocatalyst was examined in the asymmetric aldol reaction of various ketones with different aromatic aldehydes under solvent-free neat conditions to afford the desired chiral anti-aldol products in good to excellent chemical yields, diastereoselectivities and enantioselectivities (up to 99%, up to syn : anti/13 : 87 dr, up to 99% ee).
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Affiliation(s)
- Rajkumar Thiyagarajan
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology 27-1 Mizumoto-cho Muroran 050-8585 Japan
| | - Zubeda Begum
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology 27-1 Mizumoto-cho Muroran 050-8585 Japan
| | - Chigusa Seki
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology 27-1 Mizumoto-cho Muroran 050-8585 Japan
| | - Yuko Okuyama
- Tohoku Medical and Pharmaceutical University 4-4-1 Komatsushima Aoba-Ku Sendai 981-8558 Japan
| | - Eunsang Kwon
- Research and Analytical Center for Giant Molecules, Graduate School of Sciences,Tohoku Medical and Pharmaceutical University 4-4-1 Komatsushima Aoba-Ku Sendai 981-8558 Japan
| | - Koji Uwai
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology 27-1 Mizumoto-cho Muroran 050-8585 Japan
| | - Michio Tokiwa
- Tokiwakai Group 62 Numajiri Tsuduri-Chou Uchigo Iwaki 973-8053 Japan
| | - Suguru Tokiwa
- Tokiwakai Group 62 Numajiri Tsuduri-Chou Uchigo Iwaki 973-8053 Japan
| | | | - Hiroto Nakano
- Division of Sustainable and Environmental Engineering, Graduate School of Engineering, Muroran Institute of Technology 27-1 Mizumoto-cho Muroran 050-8585 Japan
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10
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Antipin IS, Alfimov MV, Arslanov VV, Burilov VA, Vatsadze SZ, Voloshin YZ, Volcho KP, Gorbatchuk VV, Gorbunova YG, Gromov SP, Dudkin SV, Zaitsev SY, Zakharova LY, Ziganshin MA, Zolotukhina AV, Kalinina MA, Karakhanov EA, Kashapov RR, Koifman OI, Konovalov AI, Korenev VS, Maksimov AL, Mamardashvili NZ, Mamardashvili GM, Martynov AG, Mustafina AR, Nugmanov RI, Ovsyannikov AS, Padnya PL, Potapov AS, Selektor SL, Sokolov MN, Solovieva SE, Stoikov II, Stuzhin PA, Suslov EV, Ushakov EN, Fedin VP, Fedorenko SV, Fedorova OA, Fedorov YV, Chvalun SN, Tsivadze AY, Shtykov SN, Shurpik DN, Shcherbina MA, Yakimova LS. Functional supramolecular systems: design and applications. RUSSIAN CHEMICAL REVIEWS 2021. [DOI: 10.1070/rcr5011] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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11
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Ma Z, Li Y, Sun XQ, Yang K, Li ZY. Calixarene Promoted Transition-Metal-Catalyzed Reactions. CHINESE J ORG CHEM 2021. [DOI: 10.6023/cjoc202012034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Yang K, Ma Z, Tong HX, Sun XQ, Hu XY, Li ZY. Asymmetric Michael addition reactions catalyzed by a novel upper-rim functionalized calix[4]squaramide organocatalyst. CHINESE CHEM LETT 2020. [DOI: 10.1016/j.cclet.2020.02.057] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Abstract
The proline-catalysed asymmetric aldol reaction is usually carried out in highly dipolar aprotic solvents (dimethylsulfoxide, dimethylformamide, acetonitrile) where proline presents an acceptable solubility. Protic solvents are generally characterized by poor stereocontrol (e.g., methanol) or poor reactivity (e.g., water). Here, we report that water/methanol mixtures are exceptionally simple and effective reaction media for the intermolecular organocatalytic aldol reaction using the simple proline as the catalyst.
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14
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Krištofíková D, Modrocká V, Mečiarová M, Šebesta R. Green Asymmetric Organocatalysis. CHEMSUSCHEM 2020; 13:2828-2858. [PMID: 32141177 DOI: 10.1002/cssc.202000137] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/05/2020] [Indexed: 06/10/2023]
Abstract
Asymmetric organocatalysis is becoming one of the main tools for the synthesis of chiral compounds that are needed as medicines, crop protection agents, and other bioactive molecules. It can be effectively combined with various green chemistry methodologies. Intensification techniques, such as ball milling, flow, high pressure, or light, bring not only higher yields, faster reactions, and easier product isolation, but also new reactivities. More sustainable reaction media, such as ionic liquids, deep eutectic solvents, green solvent alternatives, and water, also considerably enhance the sustainability profile of many organocatalytic reactions.
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Affiliation(s)
- Dominika Krištofíková
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
| | - Viktória Modrocká
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
| | - Mária Mečiarová
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
| | - Radovan Šebesta
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
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15
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Félix ARG, Simões PR, Sousa FJ, Serra MES, Murtinho D. Chiral Thiazolidine based Organocatalysts: Synthesis and Application in Asymmetric Aldol Reactions. LETT ORG CHEM 2020. [DOI: 10.2174/2210681209666190807155816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Several novel chiral organocatalysts derived from thiazolidines containing amide and thioureia
functionalities were synthesized in good yields. These organocatalysts were tested in the asymmetric
aldol reaction of acetone with p-nitrobenzaldehyde. Reaction parameters such as reaction time, catalyst
loading and solvent were optimized. Products with conversions up to 84% and enantiomeric ratios
(er) up to 84.5:15.5 (R:S) were obtained. The effect of several chiral and non-chiral additives on the
reactivity and selectivity of the reaction was also evaluated. The reaction was extended to other aromatic
aldehydes with the best organocatalyst and when p-bromobenzaldehyde was used, an er of
94.5:5.5 (R:S) was obtained.
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Affiliation(s)
- Ana Rita G. Félix
- CQC, Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | - Pedro R.D. Simões
- CQC, Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | | | | | - Dina Murtinho
- CQC, Department of Chemistry, University of Coimbra, Coimbra, Portugal
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16
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Pekachaki HM, Taghvaei-Ganjali S, Motiee F, Saber-Tehrani M. APPLICATION OF CALIXARENE DERIVATIVES AS TACKIFIER RESIN IN RUBBER COMPOUNDS FOR TIRE APPLICATIONS. RUBBER CHEMISTRY AND TECHNOLOGY 2019. [DOI: 10.5254/rct.19.81510] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
ABSTRACT
The effect of p-tert-Butylcalix[4]arene on rubber-nylon-6 fabric and rubber-metal bead wire adhesion strength was quantified. For this purpose, two typically used rubber compounds were employed for two reinforcing motorcycle tire components: ply and bead. The standard pull-out tests of rubber–fabric and rubber–metal showed improvements in adhesion strength by incorporating p-tert-Butylcalix[4]arene into rubber compounds. However, the maximum values of adhesion force to pull the polyamide fabrics and brass-coated metal wires out of the rubber compounds were observed when only 1.0 phr of p-tert-Butylcalix[4]arene was used. The adhesion performance of both fabric and metal wire decreased with higher loading amounts of p-tert-Butylcalix[4]arene. The effect of a commercial phenolic tackifying resin was also evaluated in bead compound. Very similar adhesion results to p-tert-Butylcalix[4]arene were obtained when using 1.0 phr phenolic resin.
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17
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Mondal A, Bhowmick KC. Asymmetric Direct Aldol Reaction Catalyzed by (1R, 2R)-(+)-1, 2- Diammonium Cyclohexane-L-tartrate in Water. CURRENT ORGANOCATALYSIS 2019. [DOI: 10.2174/2213337206666181227151140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
A cheap and commercially available organocatalyst, (1R, 2R)-(+)-1, 2-
diammonium cyclohexane-L-tartrate 1 was applied in direct aldol reaction in water. The organocatalyst
1 afforded aldol products from cyclohexanone and substituted aromatic aldehydes with high
yield (up to 90%) and good stereoselectivity (up to 99% ee and up to 11.5:1 dr) in large volume of
water (10 ml).
Methods:
The same aldol reaction when carried out in the presence of more expensive organocatalyst
e.g. (1R, 2R)-(+)-1,2-diaminocyclohexane and 1,6-hexanediaoic acid as acid additive furnished the
aldol products with only 20% yield, 2:1 anti/syn ratio and 92% ee.
Results and Conclusion:
In summary, we have applied a reasonably cheap and commercially available
organocatalyst 1 for highly enantioselective direct aldol reaction in water at room temperature.
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Affiliation(s)
- Anirban Mondal
- Division of Organic Synthesis, Department of Chemistry, Visva-Bharati (A Central University), Santiniketan-731 235, West Bengal, India
| | - Kartick Chandra Bhowmick
- Division of Organic Synthesis, Department of Chemistry, Visva-Bharati (A Central University), Santiniketan-731 235, West Bengal, India
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18
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Mouarrawis V, Plessius R, van der Vlugt JI, Reek JNH. Confinement Effects in Catalysis Using Well-Defined Materials and Cages. Front Chem 2018; 6:623. [PMID: 30622940 PMCID: PMC6308152 DOI: 10.3389/fchem.2018.00623] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 11/30/2018] [Indexed: 11/28/2022] Open
Abstract
This review focuses on the effects that confinement of molecular and heterogeneous catalysts with well-defined structure has on the selectivity and activity of these systems. A general introduction about catalysis and how the working principles of enzymes can be used as a source of inspiration for the preparation of catalysts with enhanced performance is provided. Subsequently, relevant studies demonstrate the importance of second coordination sphere effects in a broad sense (in homogeneous and heterogeneous catalysis). Firstly, we discuss examples involving zeolites, MOFs and COFs as heterogeneous catalysts with well-defined structures where confinement influences catalytic performance. Then, specific cases of homogeneous catalysts where non-covalent interactions determine the selectivity and activity are treated in detail. This includes examples based on cyclodextrins, calix[n]arenes, cucurbit[n]urils, and self-assembled container molecules. Throughout the review, the impact of confined spaces is emphasized and put into context, in order to get a better understanding of the effects of confinement on catalyst performance. In addition, this analysis intends to showcase the similarities between homogeneous and heterogeneous catalysts, which may aid the development of novel strategies.
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Affiliation(s)
| | | | - Jarl Ivar van der Vlugt
- Homogeneous, Supramolecular and Bio-Inspired Catalysis (HomKat) Group, Van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Amsterdam, Netherlands
| | - Joost N. H. Reek
- Homogeneous, Supramolecular and Bio-Inspired Catalysis (HomKat) Group, Van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Amsterdam, Netherlands
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19
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Ruíz-Pérez KM, Quiroz-García B, Hernández-Rodríguez M. Prolinamides of Aminouracils, Organocatalyst Modifiable by Complementary Modules. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800886] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Karen M. Ruíz-Pérez
- Instituto de Química; Universidad Nacional Autónoma de México. Circuito Exterior; Ciudad Universitaria, Del. Coyoacán, C.P. 04510 México Cd. Mx. México
| | - Beatriz Quiroz-García
- Instituto de Química; Universidad Nacional Autónoma de México. Circuito Exterior; Ciudad Universitaria, Del. Coyoacán, C.P. 04510 México Cd. Mx. México
| | - Marcos Hernández-Rodríguez
- Instituto de Química; Universidad Nacional Autónoma de México. Circuito Exterior; Ciudad Universitaria, Del. Coyoacán, C.P. 04510 México Cd. Mx. México
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20
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Owolabi IA, Subba Reddy U, Chennapuram M, Seki C, Okuyama Y, Kwon E, Uwai K, Tokiwa M, Takeshita M, Nakano H. A new type of amino amide organocatalyzed enantioselective crossed aldol reaction of ketones with aromatic aldehydes. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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21
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Bhowmick S, Zhang L, Ouyang G, Liu M. Self-Assembly of Amphiphilic Dipeptide with Homo- and Heterochiral Centers and Their Application in Asymmetric Aldol Reaction. ACS OMEGA 2018; 3:8329-8336. [PMID: 31458965 PMCID: PMC6644911 DOI: 10.1021/acsomega.8b00852] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 07/13/2018] [Indexed: 06/09/2023]
Abstract
Chiral self-assembly has drawn increasing interest in supramolecular chemistry. Here, we have designed amphiphilic l-Pro-l-Glu and l-Pro-d-Glu dipeptides and investigated their chiral self-assembly as well as asymmetric catalytic performance to disclose the synergistic effect of two stereogenic centers in the self-assembly and catalysis. It was found that both of the diastereomeric dipeptides can easily self-assemble into organogels with nanofibers. When these nanofibers were used as a catalyst for the asymmetric aldol reactions, enhanced enantioselectivity was obtained compared with their molecular state. Moreover, the L-L isomer assemblies showed higher enantioselectivity than the L-D isomer. It was revealed that both the supramolecular chirality of the nanofiber and the chiral catalytic site of l-proline played important roles in the asymmetric catalysis. In addition, the synergistic effect of two homochiral centers led to more efficient supramolecular catalysis that the L-L assemblies showed high yields (up to 97%), anti-diastereoselectivity (up to 99%), and excellent enantioselectivity (up to >99%).
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Affiliation(s)
- Sudipto Bhowmick
- Beijing
National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory
of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun Beiyijie No. 2, Haidian, Beijing 100190, P. R.
China
| | - Li Zhang
- Beijing
National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory
of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun Beiyijie No. 2, Haidian, Beijing 100190, P. R.
China
| | - Guanghui Ouyang
- Beijing
National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory
of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun Beiyijie No. 2, Haidian, Beijing 100190, P. R.
China
| | - Minghua Liu
- Beijing
National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory
of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun Beiyijie No. 2, Haidian, Beijing 100190, P. R.
China
- National
Center for Nanoscience and Technology, Zhongguancun Beiyitiao No. 11,
Haidian, Beijing 100190, P. R. China
- Collaborative
Innovation Center of Chemical Science and Engineering, Tianjin 300072, P. R. China
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Li ZY, Tong HX, Chen Y, Su HK, Xiao T, Sun XQ, Wang L. Asymmetric Michael addition reactions catalyzed by calix[4]thiourea cyclohexanediamine derivatives. Beilstein J Org Chem 2018; 14:1901-1907. [PMID: 30112095 PMCID: PMC6071695 DOI: 10.3762/bjoc.14.164] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 06/29/2018] [Indexed: 12/19/2022] Open
Abstract
A number of upper rim-functionalized calix[4]thiourea cyclohexanediamine derivatives have been designed, synthesized and used as catalysts for enantioselective Michael addition reactions between nitroolefins and acetylacetone. The optimal catalyst 2 with a mono-thiourea group exhibited good performance in the presence of water/toluene (v/v = 1:2). Under the optimal reaction conditions, high yields of up to 99% and moderate to good enantioselectivities up to 94% ee were achieved. Detailed experiments clearly showed that the upper rim-functionalized hydrophobic calixarene scaffold played an important role in cooperation with the catalytic center to the good reactivities and enantioselectivities.
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Affiliation(s)
- Zheng-Yi Li
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Hong-Xiao Tong
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Yuan Chen
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hong-Kui Su
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Tangxin Xiao
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Xiao-Qiang Sun
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Leyong Wang
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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23
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De Simone NA, Meninno S, Talotta C, Gaeta C, Neri P, Lattanzi A. Solvent-Free Enantioselective Michael Reactions Catalyzed by a Calixarene-Based Primary Amine Thiourea. J Org Chem 2018; 83:10318-10325. [PMID: 29961331 DOI: 10.1021/acs.joc.8b01454] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
An upper-rim functionalized calix[4]arene-based thiourea installed onto the ( R, R)-1,2-cyclohexanediamine scaffold was synthesized with a view to investigate its catalytic ability in enantioselective Michael additions. The reactions were found to conveniently proceed under solvent-free conditions, observing good to high enantioselectivities. From this preliminary study, the calix[4]arene unit is likely to play a role in affecting the conversion and to a lesser extent to the stereochemical outcome of the reactions through van der Waals contacts and C-H···π interactions with the substrates.
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Affiliation(s)
- Nicola Alessandro De Simone
- Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II, 132 , I-84084 Fisciano (Salerno) , Italy
| | - Sara Meninno
- Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II, 132 , I-84084 Fisciano (Salerno) , Italy
| | - Carmen Talotta
- Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II, 132 , I-84084 Fisciano (Salerno) , Italy
| | - Carmine Gaeta
- Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II, 132 , I-84084 Fisciano (Salerno) , Italy
| | - Placido Neri
- Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II, 132 , I-84084 Fisciano (Salerno) , Italy
| | - Alessandra Lattanzi
- Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II, 132 , I-84084 Fisciano (Salerno) , Italy
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24
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Hirose M, Fujiwara S, Ishigami T, Suga K, Okamoto Y, Umakoshi H. Liposome Membranes Assist the l-Proline-catalyzed Aldol Reaction of Acetone and p-Nitrobenzaldehyde in Water. CHEM LETT 2018. [DOI: 10.1246/cl.180180] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Masanori Hirose
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Shimpei Fujiwara
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Takaaki Ishigami
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Yukihiro Okamoto
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
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25
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Li ZY, Su HK, Tong HX, Yin Y, Xiao T, Sun XQ, Jiang J, Wang L. Calix[4]arene containing thiourea and coumarin functionality as highly selective fluorescent and colorimetric chemosensor for fluoride ion. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 200:307-312. [PMID: 29704730 DOI: 10.1016/j.saa.2018.04.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/04/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
A novel calix[4]arene based chemosensor L which contains coumarin and thiourea group has been synthesized and characterized. Interestingly, probe L exhibits both fluorescent and colorimetric response to fluoride anion with high selectivity and sensitivity. The addition of F- to a solution of probe L resulted in obvious naked-eye color change from colorless to orange under daylight and prominent fluorescence quenching. Further studies showed that the recognition process was less affected by other anions. The binding property of L with F- was studied by a combination of combination of various spectroscopic techniques, such as absorption spectra, fluorescence titration, Job's plot and 1H NMR titration. We are anticipating that this architecture with functional group attached to upper rim of calix[4]arene platform may provide a new approach for the development of F- chemosensor.
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Affiliation(s)
- Zheng-Yi Li
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Hong-Kui Su
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Hong-Xiao Tong
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Yue Yin
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Tangxin Xiao
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Xiao-Qiang Sun
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Juli Jiang
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China; Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Leyong Wang
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China; Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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26
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Durmaz M, Halay E, Bozkurt S. Recent applications of chiral calixarenes in asymmetric catalysis. Beilstein J Org Chem 2018; 14:1389-1412. [PMID: 29977403 PMCID: PMC6009176 DOI: 10.3762/bjoc.14.117] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 05/17/2018] [Indexed: 12/13/2022] Open
Abstract
The use of calixarenes in asymmetric catalysis is receiving increasing attention due to their tunable three-dimensional molecular platforms along with their easy syntheses and versatile modification at the upper and lower rims. This review summarizes the recent progress of synthesis and use of chiral calixarenes in asymmetric syntheses which emerged later than 2010.
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Affiliation(s)
- Mustafa Durmaz
- Department of Chemistry Education, Ahmet Kelesoglu Education Faculty, Necmettin Erbakan University, 42090 Konya, Turkey
| | - Erkan Halay
- Department of Chemistry and Chemical Processing Technologies, Banaz Vocational School, Usak University, Usak, Turkey.,Scientific Analysis Technological Application and Research Center (UBATAM), Usak University, Usak, Turkey
| | - Selahattin Bozkurt
- Scientific Analysis Technological Application and Research Center (UBATAM), Usak University, Usak, Turkey.,Vocational School of Health Services, Usak University, 64200 Usak, Turkey
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27
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De Rosa M, La Manna P, Talotta C, Soriente A, Gaeta C, Neri P. Supramolecular Organocatalysis in Water Mediated by Macrocyclic Compounds. Front Chem 2018; 6:84. [PMID: 29666791 PMCID: PMC5891620 DOI: 10.3389/fchem.2018.00084] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 03/12/2018] [Indexed: 11/20/2022] Open
Abstract
In the last decades many efforts have been devoted to design supramolecular organocatalysts able to work in water as the reaction medium. The use of water as solvent provides promising benefits with respect to environmental impact. In this context, macrocyclic compounds played a role of primary importance thanks to their ease of synthesis and their molecular recognition abilities toward the reactants. The aim of this review is to give an overview of the recent advances in the field of supramolecular organocatalysis in water, focusing the attention on calixarene and cyclodextrins derivatives. Calixarenes and cyclodextrins, thanks to their hydrophobic cavities, are able to host selectively the substrates isolating they from the reaction environment. In addition, the synthetic versatilities of these macrocycles permits to introduce useful functional groups in close proximity of the hydrophobic binding sites. Regarding the cyclodextrins (CDs), we have here reviewed the their most recent uses as organocatalysts for the synthesis of heterocyclic compounds, in multi-component reactions and in carbon-carbon bond forming reactions. Examples have been reported in which CD catalysts are able to drive the regiochemistry of common organic reactions. In addition, cyclodextrins bearing catalytically active chiral groups, have shown excellent enantioselectivity in the catalysis of organic reactions. Recently reported results have shown that calixarene derivatives are able to accelerate organic reaction under “on-water” conditions with a significant selectivity toward the reactants. Under “on-water conditions” the hydrophobic effect, induced by insoluble calixarene derivatives, forces the reactants and the catalyst to aggregate and thus accelerating the reaction between them thanks to an amplification of weak secondary interactions. Regarding the use of water-soluble calixarene organocatalysts, we have here reviewed their role in the acceleration of common organic reactions.
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Affiliation(s)
- Margherita De Rosa
- Dipartimento di Chimica e Biologia " Zambelli", Università degli Studi di Salerno, Salerno, Italy
| | - Pellegrino La Manna
- Dipartimento di Chimica e Biologia " Zambelli", Università degli Studi di Salerno, Salerno, Italy
| | - Carmen Talotta
- Dipartimento di Chimica e Biologia " Zambelli", Università degli Studi di Salerno, Salerno, Italy
| | - Annunziata Soriente
- Dipartimento di Chimica e Biologia " Zambelli", Università degli Studi di Salerno, Salerno, Italy
| | - Carmine Gaeta
- Dipartimento di Chimica e Biologia " Zambelli", Università degli Studi di Salerno, Salerno, Italy
| | - Placido Neri
- Dipartimento di Chimica e Biologia " Zambelli", Università degli Studi di Salerno, Salerno, Italy
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28
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Russo M, Lo Meo P. Binding abilities of a chiral calix[4]resorcinarene: a polarimetric investigation on a complex case of study. Beilstein J Org Chem 2018; 13:2698-2709. [PMID: 29564007 PMCID: PMC5753176 DOI: 10.3762/bjoc.13.268] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 11/30/2017] [Indexed: 11/23/2022] Open
Abstract
Polarimetry was used to investigate the binding abilities of a chiral calix[4]resorcinarene derivative, bearing L-proline subunits, towards a set of suitably selected organic guests. The simultaneous formation of 1:1 and 2:1 host–guest inclusion complexes was observed in several cases, depending on both the charge status of the host and the structure of the guest. Thus, the use of the polarimetric method was thoroughly revisited, in order to keep into account the occurrence of multiple equilibria. Our data indicate that the stability of the host–guest complexes is affected by an interplay between Coulomb interactions, π–π interactions, desolvation effects and entropy-unfavorable conformational dynamic restraints. Polarimetry is confirmed as a very useful and versatile tool for the investigation of supramolecular interactions with chiral hosts, even in complex systems involving multiple equilibria.
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Affiliation(s)
- Marco Russo
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), University of Palermo, V.le delle Scienze ed. 17, 90128 Palermo, Italy
| | - Paolo Lo Meo
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), University of Palermo, V.le delle Scienze ed. 17, 90128 Palermo, Italy.,ATeNCenter, University of Palermo, V.le delle Scienze ed. 18, 90128 Palermo, Italy
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29
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Yan CX, Zhou PP, Yang FL, Wu RZ, Yang X, Yang F, Shao X. Chiral bisoxazoline catalyzed decarboxylative aldol reactions between β-carbonyl acids and trifluoroacetaldehyde hemiacetals as well as trifluoroacetaldehyde: the mechanism, the origin of enantioselectivity and the role of a catalyst. Org Chem Front 2018. [DOI: 10.1039/c8qo00578h] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The role of a catalyst in the decarboxylative aldol reactions between β-carbonyl acids and trifluoroacetaldehyde hemiacetals as well as trifluoroacetaldehyde catalyzed by chiral bisoxazoline were unveiled theoretically.
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Affiliation(s)
- Chao-Xian Yan
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
| | - Pan-Pan Zhou
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
| | - Fang-Ling Yang
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
| | - Rui-Zhi Wu
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
| | - Xing Yang
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
| | - Fan Yang
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
| | - Xiangfeng Shao
- State Key Laboratory of Applied Organic Chemistry
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
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30
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Martins FT, Oliveira BGD, Sarotti AM, de Fátima Â. Winged-Cone Conformation in Hexa- p-tert-butylcalix[6]arene Driven by the Unusually Strong Guest Encapsulation. ACS OMEGA 2017; 2:5315-5323. [PMID: 31457800 PMCID: PMC6641646 DOI: 10.1021/acsomega.7b00900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/21/2017] [Indexed: 06/10/2023]
Abstract
Hexa-p-tert-butylcalix[6]arene (1) is believed to adopt a winged conformation in a solution, featured by four phenyl rings perpendicular to the calix basis and two others at 1,4-positions lying down. However, there is some controversy on the occurrence of this conformation because it has never been found in the solid state of calix[6]arenes, regardless of the substitution pattern at lower and upper rims. Here, we have observed the winged-cone conformation for the first time in a solvate form of 1 with dimethyl sulfoxide (DMSO), dimethylformamide, and pyridine. The DMSO molecule is strongly encapsulated into 1 through two OH···O hydrogen bonds with both flattened phenolic moieties, one lp(S)···π and four CH···π interactions with the four perpendicular phenyl rings. This host-guest complex has energy lower by 23.4 kcal mol-1 than the isolated species. In addition, another DMSO solvate form with 1,2,3-alternate conformation was also obtained in this study, and its structure is compared with that of the precedent one. A detailed density functional theory study has also been carried out to understand the energetic relationships among cone conformers, intramolecular hydrogen-bonding patterns, and DMSO encapsulation.
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Affiliation(s)
- Felipe Terra Martins
- Instituto
de Química, Universidade Federal
de Goiás, P.O. Box 131, 74690-900 Goiânia, Brazil
- Grupo
de Estudos em Química Orgânica e Biológica (GEQOB),
Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos
6627, 31270-901 Belo Horizonte, Brazil
| | - Breno Germano de
Freitas Oliveira
- Grupo
de Estudos em Química Orgânica e Biológica (GEQOB),
Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos
6627, 31270-901 Belo Horizonte, Brazil
| | - Ariel M. Sarotti
- Instituto
de Química Rosario (IQUIR), Universidad
Nacional de Rosario-CONICET, Suipacha 531, S2002LRK Rosario, Argentina
| | - Ângelo de Fátima
- Grupo
de Estudos em Química Orgânica e Biológica (GEQOB),
Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos
6627, 31270-901 Belo Horizonte, Brazil
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