TY - JOUR
T1 - Synthesis and relaxometric properties of gadolinium(III) complexes of new triazine-based polydentate ligands
AU - Tei, Lorenzo
AU - Benzi, Marina
AU - Kielar, Filip
AU - Botta, Mauro
AU - Cavallotti, Camilla
AU - Giovenzana, Giovanni Battista
AU - Aime, Silvio
PY - 2009/11
Y1 - 2009/11
N2 - Two new derivatives based on an s-triazine structural motif were synthesized by attaching two 2,2′-hydrazinylidenebis[acetic acid] moieties to the triazine ring to reach an overall heptadenticity for the complexation of lanthanide(III) cations. The remaining reactive site was exploited for the substitution with a functionizable amino group (see H 4L1) and a lipophilic moiety (see H 4L2). Luminescence-lifetime determinations revealed the presence of a single H 2O molecule coordinated for [Eu(L1)]. A complete 1H-NMR relaxometric study was carried out for the octacoordinated [Gd(L1)] and [Gd(L2)] complexes. A remarkably long H 2O residence lifetime ( 298τ M=5.2 μs) was found by 17O-NMR in the case of [Gd(L1)]. Micelle formation of the lipophilic complex [Gd(L2)] was evidenced, the critical micellization concentration (cmc) determined, and relaxometric properties of the system investigated.
AB - Two new derivatives based on an s-triazine structural motif were synthesized by attaching two 2,2′-hydrazinylidenebis[acetic acid] moieties to the triazine ring to reach an overall heptadenticity for the complexation of lanthanide(III) cations. The remaining reactive site was exploited for the substitution with a functionizable amino group (see H 4L1) and a lipophilic moiety (see H 4L2). Luminescence-lifetime determinations revealed the presence of a single H 2O molecule coordinated for [Eu(L1)]. A complete 1H-NMR relaxometric study was carried out for the octacoordinated [Gd(L1)] and [Gd(L2)] complexes. A remarkably long H 2O residence lifetime ( 298τ M=5.2 μs) was found by 17O-NMR in the case of [Gd(L1)]. Micelle formation of the lipophilic complex [Gd(L2)] was evidenced, the critical micellization concentration (cmc) determined, and relaxometric properties of the system investigated.
UR - http://www.scopus.com/inward/record.url?scp=73449131890&partnerID=8YFLogxK
U2 - 10.1002/hlca.200900189
DO - 10.1002/hlca.200900189
M3 - Article
SN - 0018-019X
VL - 92
SP - 2414
EP - 2426
JO - Helvetica Chimica Acta
JF - Helvetica Chimica Acta
IS - 11
ER -