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Vosegaard ES, Thomsen MK, Krause L, Grønbech TBE, Mamakhel A, Takahashi S, Nishibori E, Iversen BB. Synchrotron X-ray Electron Density Analysis of Chemical Bonding in the Graphitic Carbon Nitride Precursor Melamine. Chemistry 2022; 28:e202201295. [PMID: 35760733 PMCID: PMC9804335 DOI: 10.1002/chem.202201295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Indexed: 01/05/2023]
Abstract
Melamine is a precursor and building block for graphitic carbon nitride (g-CN) materials, a group of layered materials showing great promise for catalytic applications. The synthetic pathway to g-CN includes a polycondensation reaction of melamine by evaporation of ammonia. Melamine molecules in the crystal organize into wave-like planes with an interlayer distance of 3.3 Å similar to that of g-CN. Here we present an extensive investigation of the experimental electron density of melamine obtained from modelling of synchrotron radiation X-ray single-crystal diffraction data measured at 25 K with special focus on the molecular geometry and intermolecular interactions. Both intra- and interlayer structures are dominated by hydrogen bonding and π-interactions. Theoretical gas-phase optimizations of the experimental molecular geometry show that bond lengths and angles for atoms in the same chemical environment (C-N bonds in the ring, amine groups) differ significantly more for the experimental geometry than for the gas-phase-optimized geometries, indicating that intermolecular interactions in the crystal affects the molecular geometry. In the experimental crystal geometry, one amine group has significantly more sp3 -like character than the others, hinting at a possible formation mechanism of g-CN. Topological analysis and energy frameworks show that the nitrogen atom in this amine group participates in weak intralayer hydrogen bonding. We hypothesize that melamine condenses to g-CN within the layers and that the unique amine group plays a key role in the condensation process.
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Affiliation(s)
- Emilie S. Vosegaard
- Department of Chemistry and iNANOAarhus UniversityLangelandsgade 1408000Aarhus CDenmark
| | - Maja K. Thomsen
- Department of Chemistry and iNANOAarhus UniversityLangelandsgade 1408000Aarhus CDenmark
| | - Lennard Krause
- Department of Chemistry and iNANOAarhus UniversityLangelandsgade 1408000Aarhus CDenmark
| | - Thomas B. E. Grønbech
- Department of Chemistry and iNANOAarhus UniversityLangelandsgade 1408000Aarhus CDenmark
| | - Aref Mamakhel
- Department of Chemistry and iNANOAarhus UniversityLangelandsgade 1408000Aarhus CDenmark
| | - Seiya Takahashi
- Department of PhysicsFaculty of Pure and Applied Sciences andTsukuba Research Center for Energy Materials Science (TREMS)University of TsukubaTsukubaIbaraki305-8571Japan
| | - Eiji Nishibori
- Department of PhysicsFaculty of Pure and Applied Sciences andTsukuba Research Center for Energy Materials Science (TREMS)University of TsukubaTsukubaIbaraki305-8571Japan
| | - Bo B. Iversen
- Department of Chemistry and iNANOAarhus UniversityLangelandsgade 1408000Aarhus CDenmark
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Marchewka M. Infrared and Raman Spectra of Bis(Melaminium) Sulfate Dihydrate. JOURNAL OF CHEMICAL RESEARCH 2019. [DOI: 10.3184/030823403103174795] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Room temperature powder infrared and Raman measurements for the new melaminium salt, bis(2,4,6-triamino-1,3,5-triazin-1-ium) sulfate dihydrate, 2C3H7N6+·SO42-·2H2O, in the crystalline state, were carried out. The vibrational spectra in the region of internal vibrations of the ions corroborate recent X-ray data of Janczak et al. Some spectral features of this new crystal are referred to those of other crystalline melaminium salts.
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Affiliation(s)
- M.K. Marchewka
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, 50-950 Wroclaw 2, P.O. Box 937, Poland
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3
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Evolution of Interatomic and Intermolecular Interactions and Polymorphism of Melamine at High Pressure. CRYSTALS 2018. [DOI: 10.3390/cryst8070265] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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4
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Yuan X, Luo K, Zhang K, He J, Zhao Y, Yu D. Combinatorial Vibration-Mode Assignment for the FTIR Spectrum of Crystalline Melamine: A Strategic Approach toward Theoretical IR Vibrational Calculations of Triazine-Based Compounds. J Phys Chem A 2016; 120:7427-33. [PMID: 27598419 DOI: 10.1021/acs.jpca.6b06015] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although polymeric graphitic carbon nitride (g-C3N4) has been widely studied as metal-free photocatalyst, the description of its structure still remains a great challenge. Fourier transform infrared (FTIR) spectroscopy can provide complementary structural information. In this paper, we reconsider the representative crystalline melamine and develop a strategic approach to theoretically calculate the IR vibrations of this triazine-based nitrogen-rich system. IR calculations were based on three different models: a single molecule, a 4-molecule unit cell, and a 32-molecule cluster, respectively. By this comparative study the contribution of the intermolecular weak interactions were elucidated in detail. An accurate and visualized description on the experimental FTIR spectrum has been further presented by a combinatorial vibration-mode assignment based on the calculated potential energy distribution of the 32-molecule cluster. The theoretical approach reported in this study opens the way to the facile and accurate assignment for IR vibrational modes of other complex triazine-based compounds, such as g-C3N4.
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Affiliation(s)
- Xiaohong Yuan
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University , Qinhuangdao 066004, P.R. China
| | - Kun Luo
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University , Qinhuangdao 066004, P.R. China
| | - Keqin Zhang
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University , Qinhuangdao 066004, P.R. China
| | - Julong He
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University , Qinhuangdao 066004, P.R. China
| | - Yuanchun Zhao
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University , Qinhuangdao 066004, P.R. China
| | - Dongli Yu
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University , Qinhuangdao 066004, P.R. China
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List M, Puchinger H, Gabriel H, Monkowius U, Schwarzinger C. N-Methylmelamines: Synthesis, Characterization, and Physical Properties. J Org Chem 2016; 81:4066-75. [PMID: 27100712 DOI: 10.1021/acs.joc.6b00355] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
N-Methylmelamines have recently gained importance as valuable compounds for manufacturing modified melamine formaldehyde resins and other polymer building blocks. A great advantage of these polymers is the reduction of the carcinogenic formaldehyde. Selecting the polymerization processes (e.g., substance polymerization, polymerization in solution) and controlling the polymerization reaction and properties of these novel materials requires knowledge of the properties of the individual melamine derivatives used as new building blocks. All possible permutations of N-methylmelamines were prepared, and reaction progress was monitored by GC/MS. 2,4,6-Tris(dimethylamino)-1,3,5-triazine was prepared to complete the series; this is, however, also a possible byproduct in various synthesis routes. The reaction conditions were optimized to obtain high yields of each derivative with the highest possible purity. The substances were characterized by NMR and IR spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray diffraction. In addition, physical properties, such as solubility, melting points, and pKb values, were determined. The number of amino-, methylamino-, and dimethylamino groups has a significant effect on these properties. In summary, we found that by increasing the number of amino- and methylamino groups, solubility and pKb increase. With increasing number of amino groups, the compounds tend to form hydrogen bonds, and thus, the melting point shifts to higher temperature ranges where they start to decompose.
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Affiliation(s)
- Manuela List
- Institute for Chemical Technology of Organic Materials, Johannes Kepler University Linz , Altenbergerstrasse 69, 4040 Linz, Austria
| | - Helmut Puchinger
- Institute for Chemical Technology of Organic Materials, Johannes Kepler University Linz , Altenbergerstrasse 69, 4040 Linz, Austria
| | - Herbert Gabriel
- Institute for Chemical Technology of Organic Materials, Johannes Kepler University Linz , Altenbergerstrasse 69, 4040 Linz, Austria
| | - Uwe Monkowius
- Institute of Inorganic Chemistry, Johannes Kepler University Linz , Altenbergerstrasse 69, 4040 Linz, Austria
| | - Clemens Schwarzinger
- Institute for Chemical Technology of Organic Materials, Johannes Kepler University Linz , Altenbergerstrasse 69, 4040 Linz, Austria
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Abstract
Protomeric tautomerism is analyzed in view of the topological charge stabilization rules. Based on Hückel molecular orbital considerations and modern DFT calculations, it was found that the branching of amino or hydroxyl groups significantly contributes to the stability of major species through the first- and second-order perturbations with respect to the isoelectronic hydrocarbon. While amino-imino tautomerism is almost completely dominated by topological charge stabilization, hydroxyl-oxo tautomerism is affected by changes in the resonance integral of C-O/C═O bonds. Nevertheless, apart from side effects such as hydrogen bonds or solvent effects, a quantitative preference rule for the prediction of the tautomeric stability can be developed using topological π-electron energetics. As well as the analyses of simple bases, applications to complex or extended systems are exemplified analyzing purine bases, polyguanide, and polyuret. The present approach can be useful in conjunction with chemical intuition that comes from conventional valence bond theory.
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Affiliation(s)
- Masashi Hatanaka
- School of Engineering, Tokyo Denki University , 5 Senju-Asahi-cho, Adachi-ku, Tokyo 120-8551, Japan
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Sangeetha V, Govindarajan M, Kanagathara N, Marchewka MK, Gunasekaran S, Anbalagan G. Structure and vibrational spectra of melaminium bis(trifluoroacetate) trihydrate: FT-IR, FT-Raman and quantum chemical calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 125:252-263. [PMID: 24556134 DOI: 10.1016/j.saa.2014.01.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/27/2013] [Accepted: 01/08/2014] [Indexed: 06/03/2023]
Abstract
Melaminium bis(trifluoroacetate) trihydrate (MTFA), an organic material has been synthesized and single crystals of MTFA have been grown by the slow solvent evaporation method at room temperature. X-ray powder diffraction analysis confirms that MTFA crystal belongs to the monoclinic system with space group P2/c. The molecular geometry, vibrational frequencies and intensity of the vibrational bands have been interpreted with the aid of structure optimization based on density functional theory (DFT) B3LYP method with 6-311G(d,p) and 6-311++G(d,p) basis sets. The X-ray diffraction data have been compared with the data of optimized molecular structure. The theoretical results show that the crystal structure can be reproduced by optimized geometry and the vibrational frequencies show good agreement with the experimental values. The nuclear magnetic resonance (NMR) chemical shift of the molecule has been calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results. HOMO-LUMO, and other related molecular and electronic properties are calculated. The Mulliken and NBO charges have also been calculated and interpreted.
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Affiliation(s)
- V Sangeetha
- Department of Physics, D.G. Vaishnav College, Chennai 600 106, India
| | - M Govindarajan
- Department of Physics, MGGA College, Mahe, U.T. Puducherry, India
| | - N Kanagathara
- Department of Physics, Vel Tech Dr. RR Dr. SR Technical University, Avadi, Chennai 600 062, India
| | - M K Marchewka
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 937, 50-950 Wroclaw 2, Poland
| | - S Gunasekaran
- St. Peters University, Avadi, Chennai 600 054, India
| | - G Anbalagan
- Department of Physics, Presidency College, Chennai 600 005, India.
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Roy B, Bairi P, Nandi AK. Supramolecular assembly of melamine and its derivatives: nanostructures to functional materials. RSC Adv 2014. [DOI: 10.1039/c3ra44524k] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Ruhmann M, Spannenberg A, Villinger A, Schulz A, Beweries T. Reactions of Titanocene with Triazines and Dicyandiamide: Formation of Novel Di- and Trinuclear Metallacyclic Complexes. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201300226] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Binoy J, Marchewka MK, Jayakumar VS. The 'partial resonance' of the ring in the NLO crystal melaminium formate: study using vibrational spectra, DFT, HOMO-LUMO and MESP mapping. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 104:97-109. [PMID: 23266682 DOI: 10.1016/j.saa.2012.11.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 11/09/2012] [Accepted: 11/15/2012] [Indexed: 06/01/2023]
Abstract
The molecular geometry and vibrational spectral investigations of melaminium formate, a potential material known for toxicity and NLO activity, has been performed. The FT IR and FT Raman spectral investigations of melaminium formate is performed aided by the computed spectra of melaminium formate, triazine, melamine, melaminium and formate ion, along with bond orders and PED, computed using the density functional method (B3LYP) with 6-31G(d) basis set and XRD data, to reveal intermolecular interactions of amino groups with neighbor formula units in the crystal, intramolecular H⋯H repulsion of amino group hydrogen with protonating hydrogen, consequent loss of resonance in the melaminium ring, restriction of resonance to N(3)C(1)N(1) moiety leading to special type resonance of the ring and the resonance structure of CO(2) group of formate ion. The 3D matrix of hyperpolarizability tensor components has been computed to quantify NLO activity of melamine, melaminium and melaminium formate and the hyperpolarizability enhancement is analyzed using computed plots of HOMO and LUMO orbitals. A new mechanism of proton transfer responsible for NLO activity has been suggested, based on anomalous IR spectral bands in the high wavenumber region. The computed MEP contour maps have been used to analyze the interaction of melaminium and formate ions in the crystal.
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Affiliation(s)
- J Binoy
- Department of Physics, Government College, Nedumangadu, Thiruvananthapuram 695 541, Kerala, India.
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11
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Makowski SJ, Lacher M, Lermer C, Schnick W. Supramolecular hydrogen-bonded structures between melamine and N-heterocycles. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.01.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Braml NE, Sattler A, Schnick W. Formation of Melamium Adducts by Pyrolysis of Thiourea or Melamine/NH4Cl Mixtures. Chemistry 2012; 18:1811-9. [DOI: 10.1002/chem.201101885] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Indexed: 11/10/2022]
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13
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SeethaLekshmi S, Guru Row TN. Propensity of formation of zipper architecture vs. Lincoln log arrangement in solvated molecular complexes of melamine with hydroxybenzoic acids. CrystEngComm 2011. [DOI: 10.1039/c1ce05179b] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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O’Dell LA, Schurko RW, Harris KJ, Autschbach J, Ratcliffe CI. Interaction Tensors and Local Dynamics in Common Structural Motifs of Nitrogen: A Solid-State 14N NMR and DFT Study. J Am Chem Soc 2010; 133:527-46. [DOI: 10.1021/ja108181y] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Luke A. O’Dell
- Steacie Institute for Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, K1A 0R6 Ontario, Canada, Department of Chemistry, University of Windsor, 401 Sunset Avenue, Windsor, N9B 3P4 Ontario, Canada, and Department of Chemistry, 312 Natural Sciences Complex, State University of New York at Buffalo, Buffalo, New York 14260-3000, United States
| | - Robert W. Schurko
- Steacie Institute for Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, K1A 0R6 Ontario, Canada, Department of Chemistry, University of Windsor, 401 Sunset Avenue, Windsor, N9B 3P4 Ontario, Canada, and Department of Chemistry, 312 Natural Sciences Complex, State University of New York at Buffalo, Buffalo, New York 14260-3000, United States
| | - Kristopher J. Harris
- Steacie Institute for Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, K1A 0R6 Ontario, Canada, Department of Chemistry, University of Windsor, 401 Sunset Avenue, Windsor, N9B 3P4 Ontario, Canada, and Department of Chemistry, 312 Natural Sciences Complex, State University of New York at Buffalo, Buffalo, New York 14260-3000, United States
| | - Jochen Autschbach
- Steacie Institute for Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, K1A 0R6 Ontario, Canada, Department of Chemistry, University of Windsor, 401 Sunset Avenue, Windsor, N9B 3P4 Ontario, Canada, and Department of Chemistry, 312 Natural Sciences Complex, State University of New York at Buffalo, Buffalo, New York 14260-3000, United States
| | - Christopher I. Ratcliffe
- Steacie Institute for Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, K1A 0R6 Ontario, Canada, Department of Chemistry, University of Windsor, 401 Sunset Avenue, Windsor, N9B 3P4 Ontario, Canada, and Department of Chemistry, 312 Natural Sciences Complex, State University of New York at Buffalo, Buffalo, New York 14260-3000, United States
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Sattler A, Pagano S, Zeuner M, Zurawski A, Gunzelmann D, Senker J, Müller-Buschbaum K, Schnick W. Melamine-melem adduct phases: investigating the thermal condensation of melamine. Chemistry 2010; 15:13161-70. [PMID: 19876968 DOI: 10.1002/chem.200901518] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
By studying the thermal condensation of melamine, we have identified three solid molecular adducts consisting of melamine C(3)N(3)(NH(2))(3) and melem C(6)N(7)(NH(2))(3) in differing molar ratios. We solved the crystal structure of 2 C(3)N(3)(NH(2))(3)C(6)N(7)(NH(2))(3) (1; C2/c; a=21.526(4), b=12.595(3), c=6.8483(14) A; beta=94.80(3) degrees ; Z=4; V=1850.2(7) A(3)), C(3)N(3)(NH(2))(3)C(6)N(7)(NH(2))(3) (2; Pcca; a=7.3280(2), b=7.4842(2), c=24.9167(8) A; Z=4; V=1366.54(7) A(3)), and C(3)N(3)(NH(2))(3)3 C(6)N(7)(NH(2))(3) (3; C2/c; a=14.370(3), b=25.809(5), c=8.1560(16) A; beta=94.62(3) degrees ; Z=4; V=3015.0(10) A(3)) by using single-crystal XRD. All syntheses were carried out in sealed glass ampoules starting from melamine. By variation of the reaction conditions in terms of temperature, pressure, and the presence of ammonia-binding metals (europium) we gained a detailed insight into the occurrence of the three adduct phases during the thermal condensation process of melamine leading to melem. A rational bulk synthesis allowed us to realize adduct phases as well as phase separation into melamine and melem under equilibrium conditions. A solid-state NMR spectroscopic investigation of adduct 1 was conducted.
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Affiliation(s)
- Andreas Sattler
- Department Chemie und Biochemie, Ludwig-Maximilians-Universität, Butenandtstrasse 5-13(D), 81377 München, Germany
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Saplinova T, Lehnert C, Böhme U, Wagler J, Kroke E. Melem- and melamine-derived iminophosphoranes. NEW J CHEM 2010. [DOI: 10.1039/b9nj00621d] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Brand H, Mayer P, Schulz A, Soller T, Villinger A. Synthesis and Structure of Monomeric, Trimeric, and Mixed Phenylcyanamides. Chem Asian J 2008; 3:1050-8. [DOI: 10.1002/asia.200700372] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Brinkmann A, Litvinov VM, Kentgens APM. Environmentally friendly flame retardants. A detailed solid-state NMR study of melamine orthophosphate. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45 Suppl 1:S231-S246. [PMID: 18157843 DOI: 10.1002/mrc.2159] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We used solid-state NMR spectroscopy to gain detailed information about the proton positions, proximities and the hydrogen-bonding network in the environmentally friendly flame retardant melamine orthophosphate (MP). High-resolution proton one- and two-dimensional solid-state NMR spectra were obtained at high external magnetic field in combination with fast magic angle spinning of the sample. Furthermore, we recorded homo- and heteronuclear correlation spectra of types (15)N–(15)N, (1)H–(13)C, (1)H–(15)N and (1)H–(31)P. In addition, we determined the geometry of the NH and NH(2) groups in MP by (15)N–(1)H heteronuclear recoupling experiments.We were able to completely assign the different isotropic chemical shifts in MP. Furthermore, we could identify the protonation of the melamine and orthophosphate moieties. The experimental results are discussed in connection with the structural model obtained by powder X-ray diffraction together with a combined molecular modeling-Rietveld refinement approach (De Ridder et al. Helv. Chim. Acta 2004; 87: 1894). We show that the geometry of the NH2 groups can only be successfully estimated by solid-state NMR.
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Affiliation(s)
- Andreas Brinkmann
- Physical Chemistry/Solid State NMR, Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands.
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Bakharev VV, Gidaspov AA. Synthesis and molecular structure of 2-methoxy-4-amino-6-dinitromethyl-1,3,5-triazines zwitterionic salts. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2007. [DOI: 10.1134/s1070428007080271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Bakharev VV, Ghidaspov AA, Utenyshev AN, Litvinov IA, Dobrynin AB. Crystalline and molecular structure of 2,4-diamino-6-dinitromethyl-1,3,5-triazine potassium salt. J STRUCT CHEM+ 2006. [DOI: 10.1007/s10947-006-0372-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Janczak J, Kubiak R. Synthesis, structure and characterisation of two 2,4-diamino-6-R-1,3,5-triazine derivatives (R=3-cyanophenyl and 4-cyanophenyl). J Mol Struct 2005. [DOI: 10.1016/j.molstruc.2005.04.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Janczak J, Kubiak R. Transformation of one of two CN groups of o-dicyanobenzene in the presence of cyanoguanidine. Crystal and gas-phase structure of 2-(2′-cyanophenyl)-4,6-diamino-1,3,5-triazine. J Mol Struct 2005. [DOI: 10.1016/j.molstruc.2004.09.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Venugopalan P, Bürgi HB. Crystal Structure and Packing of 1-(4, 6-Diamino-1, 3, 5-triazin-2-yl)guanidinium nitrate. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19940770602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Willner I, Rosengaus J, Eichen Y. Effects controlling the conformational selectivity and association parameters of H-bonded assemblies between di- and triaminotriazines and bemegride. J PHYS ORG CHEM 2004. [DOI: 10.1002/poc.610060106] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Brodski V, Peschar R, Schenk H, Brinkmann A, van Eck ERH, Kentgens APM, Coussens B, Braam A. Structure of Melaminium Dihydrogenpyrophosphate and Its Formation from Melaminium Dihydrogenphosphate Studied with Powder Diffraction Data, Solid-State NMR, and Theoretical Calculations. J Phys Chem B 2004. [DOI: 10.1021/jp047625u] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Vladimir Brodski
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - René Peschar
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - Henk Schenk
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - Andreas Brinkmann
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - Ernst R. H. van Eck
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - Arno P. M. Kentgens
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - Betty Coussens
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
| | - Ad Braam
- Universiteit van Amsterdam, van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Nieuwe Achtergracht 166, NL-1018WV Amsterdam, The Netherlands, University of Nijmegen, Physical Chemistry/Solid State NMR, NSRIM Center, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands, and DSM Research, Postbus 18, 6160 MD, Geleen, The Netherlands
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Jürgens B, Irran E, Senker J, Kroll P, Müller H, Schnick W. Melem (2,5,8-triamino-tri-s-triazine), an important intermediate during condensation of melamine rings to graphitic carbon nitride: synthesis, structure determination by X-ray powder diffractometry, solid-state NMR, and theoretical studies. J Am Chem Soc 2003; 125:10288-300. [PMID: 12926953 DOI: 10.1021/ja0357689] [Citation(s) in RCA: 519] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Single-phase melem (2,5,8-triamino-tri-s-triazine) C(6)N(7)(NH(2))(3) was obtained as a crystalline powder by thermal treatment of different less condensed C-N-H compounds (e.g., melamine C(3)N(3)(NH(2))(3), dicyandiamide H(4)C(2)N(4), ammonium dicyanamide NH(4)[N(CN)(2)], or cyanamide H(2)CN(2), respectively) at temperatures up to 450 degrees C in sealed glass ampules. The crystal structure was determined ab initio by X-ray powder diffractometry (Cu K alpha(1): P2(1)/c (No. 14), a = 739.92(1) pm, b = 865.28(3) pm, c = 1338.16(4) pm, beta = 99.912(2) degrees, and Z = 4). In the solid, melem consists of nearly planar C(6)N(7)(NH(2))(3) molecules which are arranged into parallel layers with an interplanar distance of 327 pm. Detailed (13)C and (15)N MAS NMR investigations were performed. The presence of the triamino form instead of other possible tautomers was confirmed by a CPPI (cross-polarization combined with polarization inversion) experiment. Furthermore, the compound was characterized using mass spectrometry, vibrational (IR, Raman), and photoluminescence spectroscopy. The structural and vibrational properties of molecular melem were theoretically studied on both the B3LYP and the MP2 level. A structural optimization in the extended state was performed employing density functional methods utilizing LDA and GGA. A good agreement was found between the observed and calculated structural parameters and also for the vibrational frequencies of melem. According to temperature-dependent X-ray powder diffractometry investigations above 560 degrees C, melem transforms into a graphite-like C-N material.
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Affiliation(s)
- Barbara Jürgens
- Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5-13 (D), D-81377 Munich, Germany
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Benson MT. Density Functional Investigation of Melamine−Formaldehyde Cross-Linking Agents. 1. Partially Substituted Melamine. Ind Eng Chem Res 2003. [DOI: 10.1021/ie020638e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael T. Benson
- Idaho National Engineering and Environmental Laboratory, P.O. Box 1625, Idaho Falls, Idaho 83415-2208
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Jürgens B, Höppe HA, Irran E, Schnick W. Transformation of ammonium dicyanamide into dicyandiamide in the solid. Inorg Chem 2002; 41:4849-51. [PMID: 12230388 DOI: 10.1021/ic025800k] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ammonium dicyanamide NH(4)[N(CN)(2)] was synthesized through aqueous ion exchange. The crystal structure was investigated by single-crystal X-ray diffraction (P2(1)/c, a = 378.67(6) pm, b = 1240.9(3) pm, c = 911.84(14) pm, beta = 91.488(18) degrees, Z = 4). It derives from the CsCl structure type. Medium strong hydrogen bonds between NH(4)(+) and [N(CN)(2)](-) ions are indicative of the observed formation of dicyandiamide H(4)C(2)N(4) during heating. According to DSC and temperature-dependent X-ray powder diffractometry, this isomerization is exothermic and occurs between 102 and 106 degrees C in the solid. The reaction represents the isolobal analogue to the classical synthesis of urea by heating NH(4)OCN. While other alkali and alkaline earth dicyanamides undergo trimerization or polymerization of their anions during heating, ammonium dicyanamide thus shows a different reactivity.
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Affiliation(s)
- Barbara Jürgens
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13 (D), D-81377 München, Germany
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Panicker CY, Varghese HT, John A, Philip D, Nogueira HIS. Vibrational spectra of melamine diborate, C3N6H62H3BO3. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2002; 58:1545-1551. [PMID: 12166723 DOI: 10.1016/s1386-1425(01)00608-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
IR and Raman spectra of melamine diborate have been recorded and analysed. Band assignments are given based on the vibrations of melamine and boric acid molecules. Three sets of frequencies observed for the N-H stretching mode region is ascribed to different types of hydrogen bonds in the amino groups of the triazine ring. Due to the lower symmetry of the melamine and boric acid molecules in the crystal, activation of inactive modes and lifting of the degeneracy of certain vibrational modes are observed. Lower symmetry of the melamine molecule in the crystal has resulted in the decrease of intensity of the Raman active melamine band around 1490 cm(-1). All the internal modes of boric acid molecule were identified. All the ring breathing modes of melamine molecule show frequency shift towards the high wavenumber side. In other words, hydrogen bonding affects the ring breathing modes of melamine.
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Jahromi S, Moosheimer U. Oxygen Barrier Coatings Based on Supramolecular Assembly of Melamine. Macromolecules 2000. [DOI: 10.1021/ma0007536] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shahab Jahromi
- DSM Research, P.O. Box 18, 6160 MD Geleen, The Netherlands
| | - Ulrich Moosheimer
- Fraunhofer-Institut Verfahrenstechnik und Verpackung, Giggenhauser Strasse 35, D-85354 Freising, Germany
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Bock H, Van TTH, Schödel H. Wechselwirkungen in Kristallen. 98. Mitt. Protonierte Hexamethylmelamin-Salze mit verschiedenen Anionen: Monomeres Tetraphenylborat, dimeres Trifluoracetat und polymeres Chlorid-Dihydrat. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/prac.19973390195] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kirillova NI, Gusev AI, Kelarev VI, Malyshev VA. Crystal and molecular structure of 2,4-bis(dimethylamino)-6-furfuryloxy-1,3,5-triazine and 2,4-dichloro-6-furfurylamino-1,3,5-triazine. J STRUCT CHEM+ 1994. [DOI: 10.1007/bf02578370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Giardini-Guidoni A, Mele A, Pizzella G, Teghil R. Laser photolysis of chlorodiaminotriazines and detection of their fragmentation and clusterization products. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/oms.1210260914] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Costa L, Camino G, Bertelli G, Locatelli R, Luda M. Thermal degradation and fire retardancy of antimony and bismuth trihalides-melamine complexes. Polym Degrad Stab 1991. [DOI: 10.1016/0141-3910(91)90111-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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