Lanthanide(III) Complexes of 2-[4,7,10-Tris(phosphonomethyl)-1,4,7,10-tetraazacyclododecan-1-yl]acetic Acid (H7DOA3P): Multinuclear-NMR and Kinetic Studies

CAMPELLO, Maria Paula, Marina BALBINA, Isabel SANTOS, Přemysl LUBAL, Radek ŠEVČÍK and Romana ŠEVČÍKOVÁ. Lanthanide(III) Complexes of 2-[4,7,10-Tris(phosphonomethyl)-1,4,7,10-tetraazacyclododecan-1-yl]acetic Acid (H7DOA3P): Multinuclear-NMR and Kinetic Studies. Helvetica Chimica Acta. Zürich, Switzerland: Verlag Helvetica Chimica Acta AG, Zürich, 2009, vol. 92, No 11, p. 2398-2413. ISSN 0018-019X.

Basic information

• Original name: Lanthanide(III) Complexes of 2-[4,7,10-Tris(phosphonomethyl)-1,4,7,10-tetraazacyclododecan-1-yl]acetic Acid (H7DOA3P): Multinuclear-NMR and Kinetic Studies
• Name in Czech: Ln(III) komplexy 2-[4,7,10-Tris(fosfonomethyl)-1,4,7,10-tetraazacyklododekan-1-yl]octové kyseliny (H7DOA3P): Multinukleární-NMR a kinetická studia
• Authors: CAMPELLO, Maria Paula (620 Portugal), Marina BALBINA (620 Portugal), Isabel SANTOS (620 Portugal), Přemysl LUBAL (203 Czech Republic, guarantor), Radek ŠEVČÍK (203 Czech Republic) and Romana ŠEVČÍKOVÁ (203 Czech Republic).
• Edition: Helvetica Chimica Acta, Zürich, Switzerland, Verlag Helvetica Chimica Acta AG, Zürich, 2009, 0018-019X.

Other information

• Original language: English
• Type of outcome: Article in a journal
• Field of Study: 10402 Inorganic and nuclear chemistry
• Country of publisher: Switzerland
• Confidentiality degree: is not subject to a state or trade secret
• WWW: URL
• Impact factor: Impact factor: 1.435
• RIV identification code: RIV/00216224:14310/09:00037429
• Organization unit: Faculty of Science
• UT WoS: 000272434000019
• Keywords (in Czech): Makrocykly; lanthanidové komplexy; NMR spektroskopie; kinetika; protonační konstanty
• Keywords in English: Macrocycles; Lanthanide complexes; NMR Spectroscopy; Kinetics; Protonation constants
• Tags: International impact, Reviewed

Abstract

The protonation constants of 2-[4,7,10-tris(phosphonomethyl)-1,4,7,10-tetraazacyclododecan-1-yl]acetic acid (H7DOA3P) and of the complexes [Ln(DOA3P)]4- (Ln=Ce, Pr, Sm, Eu, and Yb) have been determined by multinuclear NMR spectroscopy in the range pD 2-13.8. Seven out of eleven protonation steps were detected (pK=13.66, 12.11, 7.19, 6.15, 5.77, 2.99, and 1.99), and the values found compare well with the ones for other related ligands. The protonation sequence for H7DOA3P was also tentatively assigned. Three protonation constants (pKMHL, pKMH2L, and pKMH3L) were determined for the lanthanide complexes. The acid-assisted dissociation of [Ln(DOA3P)]4- (Ln=Ce, Eu), in the region cH+=0.05-3.00 mol dm-3 and at different temperatures (25-60 degrees of Celsius), indicated that they have slightly the same kinetic inertness, being the [Eu(H2O)9]3+ aqua ion the final product for europium. The rates of complex formation for [Ln(DOA3P)]4- (Ln=Ce, Eu) were studied by UV/VIS spectroscopy in the pH range 5.6-6.8.

Abstract (in Czech)

Protonační konstanty uvedeného ligandu H7DOA3P a jeho komplexů [Ln(DOA3P)]4- (Ln=Ce, Pr, Sm, Eu, and Yb) byly stanoveny pomocí multinukleární NMR spektroskopie v rozsahu pD 2-13.8. Sedm z 11 protonačních kroků bylo detekováno (pK=13.66, 12.11, 7.19, 6.15, 5.77, 2.99, and 1.99) a nalezené hodnoty byly porovnány s těmi stanovenými pro analogické ligandy. Bylo navrženo taktéž protonační schema ligandu. Tři protonační konstanty (pKMHL, pKMH2L, and pKMH3L) byly stanoveny pro Ln(III) komplexy. Kysele katalyzovaný rozklad [Ln(DOA3P)]4- komplexů (Ln=Ce, Eu), v oblasti cH+=0.05-3.00 mol dm-3 a rozdílných teplotách (25-60 st. C), ukazuji na na podobnou kinetickou inertnost, kdy [Eu(H2O)9]3+ aqua ion je konečný produkt disociační reakce. Rychlost vzniku komplexů [Ln(DOA3P)]4- (Ln=Ce, Eu) byly studovány pomocí UV/VIS spektroskopie v rozsahu pH 5.6-6.8.

Links

• OC 179, research and development project: Name: Molekulární zobrazování založené na systémech obsahujících kovy.