Patrick Eulgem - Academia.edu (original) (raw)

Papers by Patrick Eulgem

Research paper thumbnail of New Rare Earth Metal Complexes with Nitrogen-Rich Ligands: 5,5′-Bitetrazolate and 1,3-Bis(tetrazol-5-yl)triazenate—On the Borderline between Coordination and the Formation of Salt-Like Compounds

Chemistry: A European Journal, Apr 18, 2008

From the two nitrogen-rich ligands BT(2-) (BT=5,5&amp... more From the two nitrogen-rich ligands BT(2-) (BT=5,5'-bitetrazole) and BTT(3-) (BTT=1,3-bis(1H-tetrazol-5-yl)triazene), a series of novel rare earth metal complexes were synthesised. For the BT ligand, a vast number of these complexes could be structurally characterised by single-crystal XRD, revealing structures ranging from discrete molecular aggregates to salt-like compounds. The isomorphous complexes [La2(BT)3]14 H2O (1) and [Ce2(BT)3]14 H2O (2) reveal discrete molecules in which one BT(2-) acts as a bridging ligand and two BT groups as chelating ligands. The complexes, [M(BT)(H2O)7]2[BT] x (x) H2O (3-5), (M=Nd (3), Sm (4), and Eu (5)), are also isomorphous and consist of [M(BT)(H2O)7]+ ions in which only one BT(2-) acts as a chelate ligand for each metal centre. [Tb(H2O)8]2[BT]3 x H2O (6) and [Er(H2O)8](2)[BT](3)x H2O (7) are salt-like compounds that do not exhibit any significant metal-nitrogen contacts. In the BTT-samarium compound 9, discrete molecules were found in which BTT(3-) acts as a tridentate ligand with three Sm--N bonds.

Research paper thumbnail of Untersuchungen zur Darstellung von Hauptgruppenelementtetrazolverbindungen zur Übertragung auf d-Elemente

Research paper thumbnail of CCDC 1409668: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Research paper thumbnail of CCDC 1052484: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Research paper thumbnail of Untersuchungen zur Darstellung von Hauptgruppenelementtetrazolverbindungen zur Übertragung auf d-Elemente

Research paper thumbnail of Syntheses and coordination chemistry of perfluoroaryl-1H-tetrazoles

Polyhedron, 2015

Abstract Attempts to prepare fluorinated 5-aryl-1H-tetrazoles by various methods were successful ... more Abstract Attempts to prepare fluorinated 5-aryl-1H-tetrazoles by various methods were successful for (3,5-bis(trifluoromethyl)phenyl)tetrazole (BTFTH) and in part for 5-pentafluoropenyltetrazole (F5PhTetH) and 5-(tetrafluoro-4-pyridinyl)tetrazole (F4PyTetH). For BTFTH, several different methods gave satisfactory yields and purity. For the other compounds, the same methods allowed only the observation of the desired species in very small quantities in ill-defined reaction product mixtures with azidodefluorination being the dominant side reaction. Negative ionising MS proved to be superior to other MS methods showing clean elimination of mainly N2 and CF2 from the tetrazolate anions. From BTFTH, the Cu complex [(BTFT)2Cu(Py)2]n could be obtained and fully characterised, including crystal structure determination (for the complex and the ligand). Magnetic and EPR data for the polymeric [(BTFT)2Cu(Py)2]n suggest that the superexchange (SE) between the Cu2+ ions (S = ½) is negligible. This can be understood by examining the crystal structure and the details of the possible SE path.

Research paper thumbnail of New Rare Earth Metal Complexes with Nitrogen-Rich Ligands: 5,5′-Bitetrazolate and 1,3-Bis(tetrazol-5-yl)triazenate—On the Borderline between Coordination and the Formation of Salt-Like Compounds

Chemistry - A European Journal, 2008

From the two nitrogen-rich ligands BT(2-) (BT=5,5&amp... more From the two nitrogen-rich ligands BT(2-) (BT=5,5'-bitetrazole) and BTT(3-) (BTT=1,3-bis(1H-tetrazol-5-yl)triazene), a series of novel rare earth metal complexes were synthesised. For the BT ligand, a vast number of these complexes could be structurally characterised by single-crystal XRD, revealing structures ranging from discrete molecular aggregates to salt-like compounds. The isomorphous complexes [La2(BT)3]14 H2O (1) and [Ce2(BT)3]14 H2O (2) reveal discrete molecules in which one BT(2-) acts as a bridging ligand and two BT groups as chelating ligands. The complexes, [M(BT)(H2O)7]2[BT] x (x) H2O (3-5), (M=Nd (3), Sm (4), and Eu (5)), are also isomorphous and consist of [M(BT)(H2O)7]+ ions in which only one BT(2-) acts as a chelate ligand for each metal centre. [Tb(H2O)8]2[BT]3 x H2O (6) and [Er(H2O)8](2)[BT](3)x H2O (7) are salt-like compounds that do not exhibit any significant metal-nitrogen contacts. In the BTT-samarium compound 9, discrete molecules were found in which BTT(3-) acts as a tridentate ligand with three Sm--N bonds.

Research paper thumbnail of New Rare Earth Metal Complexes with Nitrogen-Rich Ligands: 5,5′-Bitetrazolate and 1,3-Bis(tetrazol-5-yl)triazenate—On the Borderline between Coordination and the Formation of Salt-Like Compounds

Chemistry: A European Journal, Apr 18, 2008

From the two nitrogen-rich ligands BT(2-) (BT=5,5&amp... more From the two nitrogen-rich ligands BT(2-) (BT=5,5'-bitetrazole) and BTT(3-) (BTT=1,3-bis(1H-tetrazol-5-yl)triazene), a series of novel rare earth metal complexes were synthesised. For the BT ligand, a vast number of these complexes could be structurally characterised by single-crystal XRD, revealing structures ranging from discrete molecular aggregates to salt-like compounds. The isomorphous complexes [La2(BT)3]14 H2O (1) and [Ce2(BT)3]14 H2O (2) reveal discrete molecules in which one BT(2-) acts as a bridging ligand and two BT groups as chelating ligands. The complexes, [M(BT)(H2O)7]2[BT] x (x) H2O (3-5), (M=Nd (3), Sm (4), and Eu (5)), are also isomorphous and consist of [M(BT)(H2O)7]+ ions in which only one BT(2-) acts as a chelate ligand for each metal centre. [Tb(H2O)8]2[BT]3 x H2O (6) and [Er(H2O)8](2)[BT](3)x H2O (7) are salt-like compounds that do not exhibit any significant metal-nitrogen contacts. In the BTT-samarium compound 9, discrete molecules were found in which BTT(3-) acts as a tridentate ligand with three Sm--N bonds.

Research paper thumbnail of Untersuchungen zur Darstellung von Hauptgruppenelementtetrazolverbindungen zur Übertragung auf d-Elemente

Research paper thumbnail of CCDC 1409668: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Research paper thumbnail of CCDC 1052484: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Research paper thumbnail of Untersuchungen zur Darstellung von Hauptgruppenelementtetrazolverbindungen zur Übertragung auf d-Elemente

Research paper thumbnail of Syntheses and coordination chemistry of perfluoroaryl-1H-tetrazoles

Polyhedron, 2015

Abstract Attempts to prepare fluorinated 5-aryl-1H-tetrazoles by various methods were successful ... more Abstract Attempts to prepare fluorinated 5-aryl-1H-tetrazoles by various methods were successful for (3,5-bis(trifluoromethyl)phenyl)tetrazole (BTFTH) and in part for 5-pentafluoropenyltetrazole (F5PhTetH) and 5-(tetrafluoro-4-pyridinyl)tetrazole (F4PyTetH). For BTFTH, several different methods gave satisfactory yields and purity. For the other compounds, the same methods allowed only the observation of the desired species in very small quantities in ill-defined reaction product mixtures with azidodefluorination being the dominant side reaction. Negative ionising MS proved to be superior to other MS methods showing clean elimination of mainly N2 and CF2 from the tetrazolate anions. From BTFTH, the Cu complex [(BTFT)2Cu(Py)2]n could be obtained and fully characterised, including crystal structure determination (for the complex and the ligand). Magnetic and EPR data for the polymeric [(BTFT)2Cu(Py)2]n suggest that the superexchange (SE) between the Cu2+ ions (S = ½) is negligible. This can be understood by examining the crystal structure and the details of the possible SE path.

Research paper thumbnail of New Rare Earth Metal Complexes with Nitrogen-Rich Ligands: 5,5′-Bitetrazolate and 1,3-Bis(tetrazol-5-yl)triazenate—On the Borderline between Coordination and the Formation of Salt-Like Compounds

Chemistry - A European Journal, 2008

From the two nitrogen-rich ligands BT(2-) (BT=5,5&amp... more From the two nitrogen-rich ligands BT(2-) (BT=5,5'-bitetrazole) and BTT(3-) (BTT=1,3-bis(1H-tetrazol-5-yl)triazene), a series of novel rare earth metal complexes were synthesised. For the BT ligand, a vast number of these complexes could be structurally characterised by single-crystal XRD, revealing structures ranging from discrete molecular aggregates to salt-like compounds. The isomorphous complexes [La2(BT)3]14 H2O (1) and [Ce2(BT)3]14 H2O (2) reveal discrete molecules in which one BT(2-) acts as a bridging ligand and two BT groups as chelating ligands. The complexes, [M(BT)(H2O)7]2[BT] x (x) H2O (3-5), (M=Nd (3), Sm (4), and Eu (5)), are also isomorphous and consist of [M(BT)(H2O)7]+ ions in which only one BT(2-) acts as a chelate ligand for each metal centre. [Tb(H2O)8]2[BT]3 x H2O (6) and [Er(H2O)8](2)[BT](3)x H2O (7) are salt-like compounds that do not exhibit any significant metal-nitrogen contacts. In the BTT-samarium compound 9, discrete molecules were found in which BTT(3-) acts as a tridentate ligand with three Sm--N bonds.