. "10.1039/c2dt32045b" . . . . . "7"^^ . . "9"^^ . . . . "http://dx.doi.org/10.1039/c2dt32045b" . . "Methylene-bis[(aminomethyl)phosphinic acids]: synthesis, acid-base and coordination properties"@en . . "David, Tom\u00E1\u0161" . . . . "[20F014D04427]" . "Methylene-bis[(aminomethyl)phosphinic acids]: synthesis, acid-base and coordination properties"@en . "Methylene-bis[(aminomethyl)phosphinic acids]: synthesis, acid-base and coordination properties" . "Luke\u0161, Ivan" . "I, P(GPP207/10/P153), S, Z(MSM0021620857)" . "7" . . . "state; ligand; analogs; pcp(2-); complexes; phosphinic acid; aqueous-solution; structural-characterization; crystal-structures; inorganic-organic hybrids"@en . . . "Three symmetrical methylene-bis[(aminomethyl)phosphinic acids] bearing different substituents on the central carbon atom, (NH2CH2) PO2H-C(R-1)(R-2)-PO2H(CH2NH2) where R-1 = OH, R-2 = Me (H2L1), R-1 = OH, R-2 = Ph (H2L2) and R-1, R-2 = H (H2L3), were synthesized. Acid-base and complexing properties of the ligands were studied in solution as well as in the solid state. The ligands show unusually high basicity of the nitrogen atoms (log K-1 = 9.5-10, log K-2 = 8.5-9) if compared with simple (aminomethyl) phosphinic acids and, consequently, high stability constants of the complexes with studied divalent metal ions. The study showed the important role of the hydroxo group attached to the central carbon atom of the geminal bis(phosphinate) moiety. Deprotonation of the hydroxo group yields the alcoholate anion which tends to play the role of a bridging ligand and induces formation of polynuclear complexes. Solid-state structures of complexes [H2N=C(NH2)(2)][Cu-2(H-1L2)(2)]CO3 center dot 10H(2)O and Li-2[Co-4(H-1L1)(3)(OH)]center dot 17.5H(2)O were determined by X-ray diffraction. The complexes show unexpected geometries forming dinuclear and cubane-like structures, respectively. The dinuclear copper(II) complex contains a bridging mu(2)-alcoholate group with the O--P(=O)-CH2-NH2 fragments of each ligand molecule chelated to the different central ion. In the cubane cobalt(II) complex, one mu(3)-hydroxide and three mu(3)-alcoholate anions are located in the cube vertices and both phosphinate groups of one ligand molecule are chelating the same cobalt(II) ion while each of its amino groups are bound to different neighbouring metal ions. All such three metal ions are bridged by the alcoholate group of a given ligand."@en . "Hermann, Petr" . "Proch\u00E1zkov\u00E1, So\u0148a" . "11310" . . . "RIV/00216208:11310/13:10139594!RIV14-GA0-11310___" . "Kub\u00ED\u010Dek, Vojt\u011Bch" . . "Three symmetrical methylene-bis[(aminomethyl)phosphinic acids] bearing different substituents on the central carbon atom, (NH2CH2) PO2H-C(R-1)(R-2)-PO2H(CH2NH2) where R-1 = OH, R-2 = Me (H2L1), R-1 = OH, R-2 = Ph (H2L2) and R-1, R-2 = H (H2L3), were synthesized. Acid-base and complexing properties of the ligands were studied in solution as well as in the solid state. The ligands show unusually high basicity of the nitrogen atoms (log K-1 = 9.5-10, log K-2 = 8.5-9) if compared with simple (aminomethyl) phosphinic acids and, consequently, high stability constants of the complexes with studied divalent metal ions. The study showed the important role of the hydroxo group attached to the central carbon atom of the geminal bis(phosphinate) moiety. Deprotonation of the hydroxo group yields the alcoholate anion which tends to play the role of a bridging ligand and induces formation of polynuclear complexes. Solid-state structures of complexes [H2N=C(NH2)(2)][Cu-2(H-1L2)(2)]CO3 center dot 10H(2)O and Li-2[Co-4(H-1L1)(3)(OH)]center dot 17.5H(2)O were determined by X-ray diffraction. The complexes show unexpected geometries forming dinuclear and cubane-like structures, respectively. The dinuclear copper(II) complex contains a bridging mu(2)-alcoholate group with the O--P(=O)-CH2-NH2 fragments of each ligand molecule chelated to the different central ion. In the cubane cobalt(II) complex, one mu(3)-hydroxide and three mu(3)-alcoholate anions are located in the cube vertices and both phosphinate groups of one ligand molecule are chelating the same cobalt(II) ion while each of its amino groups are bound to different neighbouring metal ions. All such three metal ions are bridged by the alcoholate group of a given ligand." . "1477-9226" . "87659" . . . "Dalton Transactions" . . . "Havl\u00ED\u010Dkov\u00E1, Jana" . . . . "GB - Spojen\u00E9 kr\u00E1lovstv\u00ED Velk\u00E9 Brit\u00E1nie a Severn\u00EDho Irska" . . . "Methylene-bis[(aminomethyl)phosphinic acids]: synthesis, acid-base and coordination properties" . "000313804200013" . . . "42" . "7"^^ . . "Kotek, Jan" . "RIV/00216208:11310/13:10139594" .