1
|
Preda G, Jung S, Pescitelli G, Cupellini L, Armspach D, Pasini D. Enabling Stereochemical Communication and Stimuli-Responsive Chiroptical Properties in Biphenyl-Capped Cyclodextrins. Chemistry 2023; 29:e202302376. [PMID: 37668555 DOI: 10.1002/chem.202302376] [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: 07/25/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/06/2023]
Abstract
Chiroptical materials are gaining increasing interest due to their innovative character and their applications in optoelectronics and data encryption technologies. Fully harnessing the potential of building blocks from the "chiral pool", such as native cyclodextrins (CDs), as they often lack chromophores suitable for the construction of materials with significant chiroptical properties. Here, we present the synthesis and characterization of a two-level molecular stack consisting of a point-chiral element (CD) and an axially chiral element (biphenyl), capable of effectively translating the overall stereochemical information contained in CDs into stimuli-responsive chiroptical properties. α- and β-permethylated CDs were efficiently capped with two different 2,2'-difunctionalized 1,1'-biphenyl units. In CD derivatives containing the rigid 2,2'-dihydroxy-1,1'-biphenyl cap, two intramolecular hydrogen bonds act synergistically as stereoselective actuators, enabling effective communication between the two levels and the transfer of nonchromophoric stereochemical information from the cyclic-oligosaccharide to the atropoisomeric cap. The chiroptical properties can be finely tuned by external stimuli such as temperature and solvent. The way chirality is transferred from the CD platform to the biphenyl cap was revealed thanks to crystallographic and computational analyses, together with electronic circular dichroism (ECD) studies.
Collapse
Affiliation(s)
- Giovanni Preda
- Department of Chemistry and INSTM Research Unit, University of Pavia, Via Taramelli 12, 27100, Pavia, Italy
- Équipe Confinement Moléculaire et Catalyse, Institut de Chimie de Strasbourg, Université de Strasbourg, UMR 7177 CNRS, 4 rue Blaise Pascal, CS90032, 67081, Strasbourg Cedex, France
| | - Sebastian Jung
- Équipe Confinement Moléculaire et Catalyse, Institut de Chimie de Strasbourg, Université de Strasbourg, UMR 7177 CNRS, 4 rue Blaise Pascal, CS90032, 67081, Strasbourg Cedex, France
| | - Gennaro Pescitelli
- Department of Chemistry and Industrial Chemistry, University of Pisa, via Moruzzi 13, 56124, Pisa, Italy
| | - Lorenzo Cupellini
- Department of Chemistry and Industrial Chemistry, University of Pisa, via Moruzzi 13, 56124, Pisa, Italy
| | - Dominique Armspach
- Équipe Confinement Moléculaire et Catalyse, Institut de Chimie de Strasbourg, Université de Strasbourg, UMR 7177 CNRS, 4 rue Blaise Pascal, CS90032, 67081, Strasbourg Cedex, France
| | - Dario Pasini
- Department of Chemistry and INSTM Research Unit, University of Pavia, Via Taramelli 12, 27100, Pavia, Italy
| |
Collapse
|
2
|
New Coumarin Dipicolinate Europium Complexes with a Rich Chemical Speciation and Tunable Luminescence. Molecules 2021; 26:molecules26051265. [PMID: 33652775 PMCID: PMC7956443 DOI: 10.3390/molecules26051265] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 02/20/2021] [Accepted: 02/22/2021] [Indexed: 11/25/2022] Open
Abstract
Europium (III) luminescent chelates possess intrinsic photophysical properties that are extremely useful in a wide range of applications. The lack of examples of coumarin-based lanthanide complexes is mainly due to poor photo-sensitization attempts. However, with the appeal of using such a versatile scaffold as antenna, especially in the development of responsive molecular probes, it is worth the effort to research new structural motifs. In this work, we present a series of two new tris coumarin-dipicolinate europium (III) complexes, specifically tailored to be either a mono or a dual emitter, tuning their properties with a simple chemical modification. We also encountered a rich chemical speciation in solution, studied in detail by means of paramagnetic NMR and emission spectroscopy.
Collapse
|
3
|
Gendron F, Di Pietro S, Abad Galán L, Riobé F, Placide V, Guy L, Zinna F, Di Bari L, Bensalah-Ledoux A, Guyot Y, Pilet G, Pointillart F, Baguenard B, Guy S, Cador O, Maury O, Le Guennic B. Luminescence, chiroptical, magnetic and ab initio crystal-field characterizations of an enantiopure helicoidal Yb(iii) complex. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01194k] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The electronic structure of a chiral Yb(iii)-based complex is fully determined by taking advantage of experimental magnetic, luminescence, and chiroptical (NIR-ECD and CPL) characterizations in combination with ab initio wavefunction calculations.
Collapse
|
4
|
Sun X, Meng F, Su Q, Luo K, Ju P, Liu Z, Li X, Li G, Wu Q. New catalytically active conjugated microporous polymer bearing ordered salen-Cu and porphyrin moieties for Henry reaction in aqueous solution. Dalton Trans 2020; 49:13582-13587. [PMID: 32970055 DOI: 10.1039/d0dt02686g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A catalytically active conjugated microporous polymer (SP-CMP-Cu) was facilely constructed with condensation polymerization of salen-Cu (salen = N,N'-bis(3-tertbutyl-5-formylsalicylidene) ethylenediamine) and pyrrole. The as-synthesized SP-CMP-Cu was completely characterized by powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray (EDX) analysis. The morphological features of SP-CMP-Cu were revealed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). According to the N2 adsorption/desorption isotherm, the Brunauer-Emmett-Teller (BET) surface area of SP-CMP-Cu was calculated to be 252 m2 g-1 with a total pore volume of 0.178 cm3 g-1. SP-CMP-Cu exhibited an outstanding catalytic performance for the Henry reaction in aqueous solutions with excellent conversion and good selectivity. Moreover, SP-CMP-Cu can be reused for up to five consecutive runs without any significant loss in its catalytic efficiency.
Collapse
Affiliation(s)
- Xiaoman Sun
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Fanyu Meng
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Qing Su
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Kexin Luo
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Pengyao Ju
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Ziqian Liu
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Xiaodong Li
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| | - Guanghua Li
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Qiaolin Wu
- College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.
| |
Collapse
|
5
|
Fan Y, Ren Y, Li J, Yue C, Jiang H. Enhanced Activity and Enantioselectivity of Henry Reaction by the Postsynthetic Reduction Modification for a Chiral Cu(salen)-Based Metal-Organic Framework. Inorg Chem 2018; 57:11986-11994. [PMID: 30199236 DOI: 10.1021/acs.inorgchem.8b01551] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Metal-organic frameworks (MOFs) imbedded privileged molecular catalysts are of particular interest due to their higher catalytic activities derived from the MOFs pore/channel confinement effect, improved lifetime through eliminating intermolecular deactivation pathway, and the recyclability based on their heterogeneity. In this work, a 3D chiral metallosalen-based MOF [Cd2(Cu(salen))(DMF)3]·DMF·3H2O (1) with a 1D open channel was synthesized and characterized by single-crystal X-ray diffraction and other physicochemical methods. Upon postsynthetic reduction modification with NaBH4, the conversion from imino to amino group on salen cores of 1 generates the reduction product 2 with a more flexible chiral group and more alkaline backbone, meanwhile still maintaining the original porous framework. 2 can be used as an efficient heterogeneous catalyst for the asymmetric Henry reaction with broad substrate applicability and exhibits higher activity and enantioselectivity (ee up to 98%) compared with the unreduced 1. Note that 2 can accelerate the Henry reaction of pyridine-2-carboxaldehyde possessing a potential coordination atom with excellent ee value; however, the homogeneous counterpart does not. In addition, the bulky aldehydes show a decrease in activity but almost the same enantioselectivity with an increase in the molecular size of substrates as a result of the chiral confinement effect of 2, indicating the size-dependent selectivity. To the best of our knowledge, this is the highest enantioselectivity for asymmetric Henry reaction catalyzed by MOF-based catalysts.
Collapse
Affiliation(s)
- Yamei Fan
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , 510641 , P. R. China
| | - Yanwei Ren
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , 510641 , P. R. China
| | - Jiawei Li
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , 510641 , P. R. China
| | - Chenglong Yue
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , 510641 , P. R. China
| | - Huanfeng Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , 510641 , P. R. China
| |
Collapse
|
6
|
Górecki M, Carpita L, Arrico L, Zinna F, Di Bari L. Chiroptical methods in a wide wavelength range for obtaining Ln 3+ complexes with circularly polarized luminescence of practical interest. Dalton Trans 2018; 47:7166-7177. [PMID: 29774898 DOI: 10.1039/c8dt00865e] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We studied enantiopure chiral trivalent lanthanide (Ln3+ = La3+, Sm3+, Eu3+, Gd3+, Tm3+, and Yb3+) complexes with two fluorinated achiral tris(β-diketonate) ligands (HFA = hexafluoroacetylacetonate and TTA = 2-thenoyltrifluoroacetonate), incorporating a chiral bis(oxazolinyl)pyridine (PyBox) unit as a neutral ancillary ligand, by the combined use of optical and chiroptical methods, ranging from UV to IR both in absorption and circular dichroism (CD), and including circularly polarized luminescence (CPL). Ultimately, all the spectroscopic information is integrated into a total and a chiroptical super-spectrum, which allows one to characterize a multidimensional chemical space, spanned by the different Ln3+ ions, the acidity and steric demand of the diketone and the chirality of the PyBox ligand. In all cases, the Ln3+ ions endow the systems with peculiar chiroptical properties, either allied to f-f transitions or induced by the metal onto the ligand. In more detail, we found that Sm3+ complexes display interesting CPL features, which partly superimpose and partly integrate the more common Eu3+ properties. Especially, in the context of security tags, the pair Sm/Eu may be a winning choice for chiroptical barcoding.
Collapse
Affiliation(s)
- Marcin Górecki
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via Moruzzi 13, 56124 Pisa, Italy.
| | | | | | | | | |
Collapse
|
7
|
Atzeri C, Marzaroli V, Quaretti M, Travis JR, Di Bari L, Zaleski CM, Tegoni M. Elucidation of 1H NMR Paramagnetic Features of Heterotrimetallic Lanthanide(III)/Manganese(III) 12-MC-4 Complexes. Inorg Chem 2017; 56:8257-8269. [PMID: 28677961 DOI: 10.1021/acs.inorgchem.7b00970] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The paramagnetic one-dimensional 1H NMR spectra of twelve LnIIINaI(OAc)4[12-MCMnIII(N)shi-4] complexes, where LnIII is PrIII-YbIII (except PmIII) and YIII, are reported. Their solid-state isostructural nature is confirmed in methanol-d4 solution, as a similar pattern in the 1H NMR spectra is observed along the series. Notably, a relatively well-resolved spectrum is reported for the GdIII complex. The chemical shift data are analyzed using the "all lanthanides" method, and the Fermi contact and pseudo-contact contributions are calculated for the lanthanide-induced shift (LIS). For the TbIII-YbIII complexes, the pseudo-contact contributions are typically 1 order of magnitude higher than the Fermi contact contributions; however, for the GdIII complex, the Fermi contact is the main contribution to the paramagnetic chemical shift. For the methyl protons of the axial acetate (-OAc) ligands, the LIS is opposite in sign, with respect to that of the aromatic salicylhydroximate (shi3-) protons, because of structural rearrangements that occur upon dissociation of the NaI cation in solution. The calculated crystal field parameters (BLn) for the TbIII (360 cm-1), DyIII (250 cm-1), HoIII (380 cm-1), ErIII (410 cm-1), TmIII (620 cm-1), and YbIII (380 cm-1) complexes are not constant, likely as a consequence of the inaccuracy of the Bleaney's constants and, to a smaller extent, the small structural changes that occur in solution. Overall, the metallacrown scaffold retains structural integrity and similarity in solution for the entire series; however, small structural features, which do not affect the overall similarity, do likely occur.
Collapse
Affiliation(s)
- Corrado Atzeri
- Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma , Parco Area delle Scienze 11A, 43124 Parma, Italy
| | - Vittoria Marzaroli
- Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma , Parco Area delle Scienze 11A, 43124 Parma, Italy
| | - Martina Quaretti
- Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma , Parco Area delle Scienze 11A, 43124 Parma, Italy
| | - Jordan R Travis
- Department of Chemistry and Biochemistry, Shippensburg University , Shippensburg, Pennsylvania 17257-2200, United States
| | - Lorenzo Di Bari
- Department of Chemistry and Industrial Chemistry, University of Pisa , Via Risorgimento 35, I-56126 Pisa, Italy
| | - Curtis M Zaleski
- Department of Chemistry and Biochemistry, Shippensburg University , Shippensburg, Pennsylvania 17257-2200, United States
| | - Matteo Tegoni
- Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma , Parco Area delle Scienze 11A, 43124 Parma, Italy
| |
Collapse
|
8
|
Robinson JR, Qiao Y, Gu J, Carroll PJ, Walsh PJ, Schelter EJ. The role of dynamic ligand exchange in the oxidation chemistry of cerium(iii). Chem Sci 2016; 7:4537-4547. [PMID: 30155100 PMCID: PMC6016327 DOI: 10.1039/c5sc04897d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/22/2016] [Indexed: 01/09/2023] Open
Abstract
We report the exchange processes and reactivity of 1-Ce(het), which establish the effects of ligand redistribution and ligand reorganization in CeIII oxidation chemistry.
The CeIII/IV couple is useful for many applications in organic, inorganic, and materials chemistry. However, attaining a general method to access both oxidations states through reversible solution redox chemistry remains challenging. Herein we report the synthesis, characterization, and oxidation chemistry of the novel Ce/Li REMB heterochiral diastereomer, 1-Ce(het). The solution exchange processes of 1-RE(het) (RE = Ce and Yb) were investigated to estimate rates of ligand and cation exchange relevant in homochiral and heterochiral frameworks. A detailed mechanistic investigation following the solution dynamics of 1-Ce(het) revealed reactivity controlled both by ligand reorganization and redistribution processes. Ligand reorganization was responsible for the kinetics associated with the chemical oxidation reaction, whereas ligand redistribution and exchange dictated the isolated products.
Collapse
Affiliation(s)
- Jerome R Robinson
- P. Roy and Diana T. Vagelos Laboratories , Department of Chemistry , University of Pennsylvania , Philadelphia , PA 19104 , USA . ;
| | - Yusen Qiao
- P. Roy and Diana T. Vagelos Laboratories , Department of Chemistry , University of Pennsylvania , Philadelphia , PA 19104 , USA . ;
| | - Jun Gu
- P. Roy and Diana T. Vagelos Laboratories , Department of Chemistry , University of Pennsylvania , Philadelphia , PA 19104 , USA . ;
| | - Patrick J Carroll
- P. Roy and Diana T. Vagelos Laboratories , Department of Chemistry , University of Pennsylvania , Philadelphia , PA 19104 , USA . ;
| | - Patrick J Walsh
- P. Roy and Diana T. Vagelos Laboratories , Department of Chemistry , University of Pennsylvania , Philadelphia , PA 19104 , USA . ;
| | - Eric J Schelter
- P. Roy and Diana T. Vagelos Laboratories , Department of Chemistry , University of Pennsylvania , Philadelphia , PA 19104 , USA . ;
| |
Collapse
|
9
|
Berardozzi R, Pescitelli G, Di Pietro S, Resta C, Ballistreri FP, Pappalardo A, Tomaselli GA, Di Bari L. Synthesis, Structural Characterization, and Chiroptical Studies of Bidentate Salen-Type Lanthanide (III) Complexes. Chirality 2015; 27:857-63. [DOI: 10.1002/chir.22499] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/19/2015] [Accepted: 07/20/2015] [Indexed: 12/18/2022]
Affiliation(s)
| | | | - Sebastiano Di Pietro
- Dipartimento di Chimica; Università di Pisa; Pisa Italy
- École Noramle Supérieure de Lyon; Lyon France
| | - Claudio Resta
- Dipartimento di Chimica; Università di Pisa; Pisa Italy
- CSGI-Dipartimento di Chimica “Ugo Schiff”; Università di Firenze; Sesto Fiorentino (FI) Italy
| | | | - Andrea Pappalardo
- Dipartimento di Scienze Chimiche; Università di Catania; Catania Italy
| | | | | |
Collapse
|
10
|
Berardozzi R, Di Bari L. Optical Activity in the Near-IR Region: Theλ=980 nm Multiplet of Chiral Yb3+Complexes. Chemphyschem 2015. [DOI: 10.1002/cphc.201500355] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
11
|
Robinson JR, Fan X, Yadav J, Carroll PJ, Wooten AJ, Pericàs MA, Schelter EJ, Walsh PJ. Air- and Water-Tolerant Rare Earth Guanidinium BINOLate Complexes as Practical Precatalysts in Multifunctional Asymmetric Catalysis. J Am Chem Soc 2014; 136:8034-41. [DOI: 10.1021/ja502568g] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Jerome R. Robinson
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Xinyuan Fan
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Jagjit Yadav
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Patrick J. Carroll
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Alfred J. Wooten
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Miquel A. Pericàs
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain
- Departament
de Química Orgànica, Universitat de Barcelona (UB), 08028 Barcelona, Spain
| | - Eric J. Schelter
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Patrick J. Walsh
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|
12
|
Jurinovich S, Pescitelli G, Di Bari L, Mennucci B. A TDDFT/MMPol/PCM model for the simulation of exciton-coupled circular dichroism spectra. Phys Chem Chem Phys 2014; 16:16407-18. [DOI: 10.1039/c3cp55428g] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A multiscale strategy is presented to simulate electronic CD spectra of multichromophoric systems using an excitonic approach in which all components are calculated self-consistently through a fully polarizable QM/MM/PCM method.
Collapse
Affiliation(s)
- Sandro Jurinovich
- Dipartimento di Chimica e Chimica Industriale
- University of Pisa
- I-56126 Pisa, Italy
| | - Gennaro Pescitelli
- Dipartimento di Chimica e Chimica Industriale
- University of Pisa
- I-56126 Pisa, Italy
| | - Lorenzo Di Bari
- Dipartimento di Chimica e Chimica Industriale
- University of Pisa
- I-56126 Pisa, Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale
- University of Pisa
- I-56126 Pisa, Italy
| |
Collapse
|
13
|
Nieto I, Wooten AJ, Robinson JR, Carroll PJ, Schelter EJ, Walsh PJ. Synthesis and Catalytic Activity of Heterobimetallic Rare Earth–Zinc Ethyl BINOLate Analogues of Shibasaki’s Catalysts. Organometallics 2013. [DOI: 10.1021/om4009444] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ismael Nieto
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Alfred J. Wooten
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Jerome R. Robinson
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Patrick J. Carroll
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Eric J. Schelter
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Patrick J. Walsh
- P.
Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| |
Collapse
|
14
|
Di Pietro S, Piano SL, Di Bari L. Pseudocontact shifts in lanthanide complexes with variable crystal field parameters. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2011.05.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
15
|
Pescitelli G, Di Bari L, Berova N. Conformational aspects in the studies of organic compounds by electronic circular dichroism. Chem Soc Rev 2011; 40:4603-25. [PMID: 21677932 DOI: 10.1039/c1cs15036g] [Citation(s) in RCA: 270] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The electronic circular dichroism (ECD) spectra of flexible molecules include the contributions of all conformers populated at the working temperature. ECD spectra of chiral substrates depend on their stereochemistry in terms of both absolute configuration, as reflected in the sign of the spectrum, and molecular conformation, which dictates the overall spectral shape (possibly including the sign) in a very sensitive manner. The unique high sensitivity of ECD towards conformation, as well as of other chiroptical spectroscopies, renders these techniques a useful alternative or complement to standard spectroscopic tools for conformational investigations, such as NMR. This tutorial review provides first a brief discussion of the main principles of ECD spectroscopy and related methods for interpretation of spectra, with special reference to conformational aspects. The review focuses on the common problems encountered in the application of ECD for assignments of absolute configuration of flexible molecules. These problems can be handled either by taking into account the whole conformational ensemble or by considering rigid derivatives prepared ad hoc. Finally, the review presents the relatively less common but very interesting application of ECD spectroscopy for conformational analyses of organic compounds.
Collapse
Affiliation(s)
- Gennaro Pescitelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via Risorgimento 35, I-56126 Pisa, Italy
| | | | | |
Collapse
|