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Shan H, Wilson WK, Kamaric E. NOESY and DFT-GIAO Calculations Reveal Pervasive Errors in C20 Configurations of Taraxastane-3,20-diols: Proposals to Improve NMR Structure Determinations. Org Lett 2020; 22:1714-1719. [DOI: 10.1021/acs.orglett.9b04566] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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2
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Jung S, Podlech J. Stereoelectronic Effects: The γ-Gauche Effect in Sulfoxides. J Phys Chem A 2018; 122:5764-5772. [DOI: 10.1021/acs.jpca.8b03729] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sebastian Jung
- Institut für Organische Chemie, Karlsruher Institut für Technologie (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Joachim Podlech
- Institut für Organische Chemie, Karlsruher Institut für Technologie (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
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Balaban AT, Young DC, Plavec J, Pečnik K, Pompe M, Dahl JE, Carlson RMK. NMR spectral properties of the tetramantanes - nanometer-sized diamondoids. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:1003-1018. [PMID: 26286373 DOI: 10.1002/mrc.4289] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 06/08/2015] [Accepted: 06/12/2015] [Indexed: 06/04/2023]
Abstract
Tetramantanes, and all diamondoid hydrocarbons, possess carbon frameworks that are superimposable upon the cubic diamond lattice. This characteristic is invaluable in assigning their (1)H and (13)C NMR spectra because it translates into repeating structural features, such as diamond-cage isobutyl moieties with distinctively complex methine to methylene signatures in COSY and HMBC data, connected to variable, but systematic linkages of methine and quaternary carbons. In all tetramantane C22H28 isomers, diamond-lattice structures result in long-range (4)JHH, W-coupling in COSY data, except where negated by symmetry; there are two highly symmetrical and one chiral tetramantane (showing seven (4)JHH). Isobutyl-cage methines of lower diamondoids and tetramantanes are the most shielded resonances in their (13)C spectra (<29.5 ppm). The isobutyl methylenes are bonded to additional methines and at least one quaternary carbon in the tetramantanes. W-couplings between these methines and methylenes clarify spin-network interconnections and detailed surface hydrogen stereochemistry. Vicinal couplings of the isobutyl methylenes reveal positions of the quaternary carbons: HMBC data then tie the more remote spin systems together. Diamondoid (13) C NMR chemical shifts are largely determined by α and β effects, however γ-shielding effects are important in [123]tetramantane. (1)H NMR chemical shifts generally correlate with numbers of 1,3-diaxial H-H interactions. Tight van der Waals contacts within [123]tetramantane's molecular groove, however, form improper hydrogen bonds, deshielding hydrogen nuclei inside the groove, while shielding those outside, indicated by Δδ of 1.47 ppm for geminal hydrogens bonded to C-3,21. These findings should be valuable in future NMR studies of diamondoids/nanodiamonds of increasing size.
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Affiliation(s)
- Alexandru T Balaban
- Texas A&M University at Galveston, Department of Marine Sciences, 200 Seawolf Parkway, Galveston, TX, 77553, USA
| | | | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Ljubljana, Slovenia
| | - Klemen Pečnik
- Slovenian NMR Centre, National Institute of Chemistry, Ljubljana, Slovenia
| | - Matevž Pompe
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, Aškerčeva 5, 1000, Ljubljana, Slovenia
| | - Jeremy E Dahl
- Stanford Institute for Materials and Energy Sciences, Stanford University, 476 Lomita Mall, Stanford, CA, 94305, USA
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Robert M K Carlson
- Stanford Institute for Materials and Energy Sciences, Stanford University, 476 Lomita Mall, Stanford, CA, 94305, USA
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
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Ulshöfer R, Wedel T, Süveges B, Podlech J. Conformationally Constrained Oxides of 1,3-Dithiane: Synthesis and NMR Spectroscopic Investigations. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200675] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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5
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Mattiza JT, Meyer VJ, Duddeck H. Stereoisomeric 2-butylphenylsulfoxides and their binding modes in the adduct formation with an enantiopure dirhodium tetracarboxylate complex. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2010.01.060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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6
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Reis MG, de Faria DA, dos Santos IA, Amaral MDCE, Marsaioli AJ. Byrsonic Acid—the Clue to Floral Mimicry Involving Oil-Producing Flowers and Oil-Collecting Bees. J Chem Ecol 2007; 33:1421-9. [PMID: 17530390 DOI: 10.1007/s10886-007-9309-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Revised: 04/23/2007] [Accepted: 05/07/2007] [Indexed: 11/24/2022]
Abstract
Tetrapedia diversipes and other Apidae (Anthophoridae) may be deceived by floral similarities between Malpighiaceae and Orchidaceae of the Oncidiinae subtribe. The latter do not usually exudate floral oils. Thus, visitors may pollinate the flowers in a deceit/food/pollination syndrome. We studied the chemical compositions of Byrsonima intermedia (Malpighiaceae) floral oil and T. diversipes (Anthophoridae) cell provisions. From B. intermedia floral oil, we isolated a novel fatty acid (3R, 7R)-3,7-diacetoxy-docosanoic acid, here named byrsonic acid, and from T diversipes cell provisions we isolated two novel fatty acid derivatives 3,7-dihydroxy-eicosanoic acid and 3,7-dihydroxy-docosanoic acid, here named tetrapedic acids A and B, respectively. The three fatty acid derivatives have common features: possess long chains (20 or 22 carbon atoms) with no double bond and either hydroxy or acetoxy groups at carbons 3 and 7. This characteristic was also encountered in the fatty acid moiety of oncidinol (2S, 3'R, 7'R)-l-acetyl-2-[3', 7'-diacetoxyeicosanyl)-glycerol, a major floral oil constituent of several Oncidiinae species (Orchidaceae). Thus, both tetrapedic A (C20) and B (C22) could be the biotransformation products of oncidinol and byrsonic acid by T. diversipes hydrolases. These are the chemical clues for bee visitation and oil collecting from both plant species. The results indicate that the deceit/pollination syndrome should not be applied to all Oncidiinae flowers.
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Affiliation(s)
- Mariza G Reis
- Instituto de Quimica, UNICAMP, C. P. 6154, 13084-971 Campinas, SP, Brazil
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Reis AKCA, Rittner R. Substituent effects in the 13C NMR chemical shifts of alpha-mono-substituted acetonitriles. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:681-5. [PMID: 16863701 DOI: 10.1016/j.saa.2006.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Accepted: 04/17/2006] [Indexed: 05/11/2023]
Abstract
13C chemical shifts empirical calculations, through a very simple additivity relationship, for the alpha-methylene carbon of some alpha-mono-substituted acetonitriles, Y-CH(2)-CN (Y=H, F, Cl, Br, I, OMe, OEt, SMe, SEt, NMe(2), NEt(2), Me and Et), lead to similar, or even better, results in comparison to the reported values obtained through Quantum Mechanics methods. The observed deviations, for some substituents, are very similar for both approaches. This divergence between experimental and calculated, either empirically or theoretically, values are smaller than for the corresponding acetones, amides, acetic acids and methyl esters, which had been named non-additivity effects (or intramolecular interaction chemical shifts, ICS) and attributed to some orbital interactions. Here, these orbital interactions do not seem to be the main reason for the non-additivity effects in the empirical calculations, which must be due solely to the magnetic anisotropy of the heavy atom present in the substituent. These deviations, which were also observed in the theoretical calculations, were attributed in that case to the non-inclusion of relativistic effects and spin-orbit coupling in the Hamiltonian. Some divergence is also observed for the cyano carbon chemical shifts, probably due to the same reasons.
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Affiliation(s)
- Adriana K C A Reis
- Physical Organic Chemistry Laboratory, Chemistry Institute, State University of Campinas, Caixa Postal 6154, 13084-971 Campinas, SP, Brazil
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Ranking the effect of [1A(ax), 1B(eq)] versus [1A(eq), 1B(ax)] cyclohexane ring substitution on the 1H chemical shifts of γ-methylene cyclohexane ring protons using 2,2-disubstituted adamantanes as models. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.01.121] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Hong SP, McIntosh MC. A simple 13 C NMR method for determination of the relative stereochemistry of 2,3-dialkylpentenoic acids and related compounds. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00349-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Rockitt S, Duddeck H, Omelanczuk J. First direct discrimination of chiral phosphorus thionate (P=S) derivatives by multinuclear magnetic resonance spectroscopy in the presence of a chiral dirhodium complex. Chirality 2001; 13:214-23. [PMID: 11284027 DOI: 10.1002/chir.1022] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Enantiomeric ratios of compounds with P=S functionalities can be determined by 1H, 13C, and 31P NMR spectroscopic inspection of their diastereomeric complexes with (R)-Rh2(MTPA)4 (MTPA-H identical with methoxytrifluoromethylphenylacetic acid; Mosher's acid). This is the first facile and rapid spectroscopic method for chiral recognition in this class of compounds. Whereas complexation shifts Deltadelta are moderate or even negligible, significant signal dispersions Delta(nu) can be observed. Some rationalization about the complexation mode is presented. The NMR spectral characteristics of the free P=S compounds 1-9 are described in detail.
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Affiliation(s)
- S Rockitt
- Hannover University, Institute of Organic Chemistry, Hannover, Germany
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Ipaktschi J, Heydari A, Kalinowski HO. Chelat-kontrollierte diastereoselektive Addition an α,ß-Epoxy-Aldehyde. ACTA ACUST UNITED AC 1994. [DOI: 10.1002/cber.19941270519] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Głowacki Z, Topolski M. 13 C NMR spectra of amino-alkylphosphonic acids. MAGNETIC RESONANCE IN CHEMISTRY : MRC 1989; 27:897-899. [PMID: 34034440 DOI: 10.1002/mrc.1260270915] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/1988] [Accepted: 02/21/1989] [Indexed: 06/12/2023]
Abstract
13 C chemical shifts and 31 P,13 C coupling constants are reported for 20 amino-alkylphosphonic acids and two phosphonic acids. The substituent-induced chemical shifts of the phosphonate group were calculated and their non-additivity in 1-aminoalkylphosphonic acids was observed. Two stable conformers of 4-aminobutylphosphonic acid were detected by 13 C NMR.
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Affiliation(s)
- Zdzislaw Głowacki
- Department of Organic Chemistry, Technical University, 80-952 Gdansk 6, Poland
| | - Marek Topolski
- Department of Organic Chemistry, Technical University, 80-952 Gdansk 6, Poland
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Schneider HJ, Buchheit U, Hoppen V, Schmidt G. 13C- and1H-NMR Shielding Effects in Aliphaticgauche/trans Fragments. ACTA ACUST UNITED AC 1989. [DOI: 10.1002/cber.19891220219] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Pachter R, Wessels PL. Intramolecular non-bonded interactions and β- and γ-hydroxy substituent 13C NMR chemical shifts. J Mol Struct 1988. [DOI: 10.1016/0022-2860(88)85030-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mikhova B, Spassov S, Popandova K, Dryanska V, Ivanov C, Duddeck H, Kaiser M. NMR spectra and stereochemistry of some 2,3,4,5-tetrasubstituted pyrrolidines. J Mol Struct 1987. [DOI: 10.1016/0022-2860(87)85077-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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