cg300415e_si_001.pdf (222.73 kB)
Toward a New Type of Multifunctional Metal–Organic Systems Based on Nucleobase Analogues: First Results Derived From The Use of Aliphatic α,ω-Dicarboxylates
journal contribution
posted on 2012-07-03, 00:00 authored by Ana B. Caballero, Antonio Rodríguez-Diéguez, Luis Lezama, Juan M. SalasFive new transition metal complexes, containing the purine-mimetic
ligands 7-amine-1,2,4-triazolo[1,5-a]pyrimidine (7atp)
and 4,5-dihydro-5-oxo-1,2,4-triazolo[1,5-a]pyrimidine
(5HtpO), and also malonate (mal2–) and succinate
(suc2–) as secondary ligands are reported. Their
formula are [Mn2(μ-7atp)2(μ-mal)2(H2O)2] (1), [Zn2(μ-7atp)2(μ-mal)2(H2O)2] (2), [Cu2(5HtpO)2(mal)2(H2mal)2(μ-H2O)2] (3), [Cu2(μ-5tpO)2(μ-Hsuc)2(H2O)2] (4), and [Cd2(μ-5tpO)2(μ4-suc)(H2O)2]n (5). Single-crystal X-ray analysis show that compounds 1–4 feature all dinuclear units with different
topologies while compound 5 exhibits a 3D-network with
small-diameter pores. The variety of coordination modes displayed
by both triazolopyrimidine derivatives together with the bridging
capability of the aliphatic α,ω-dicarboxylates used lead
to compounds with interesting structural features and physical properties.
The Cu(II) malonate dimer 3 exhibits weak ferromagnetic
interactions (J = +1.5 cm–1) while
a weak and a moderately strong antiferromagnetism are displayed, respectively,
in the Mn(II) (J = −2.1 cm–1) and Cu(II) succinate dimer 4 (J =
−109.7 cm–1). On the other hand, solid-state
photoluminescent emission is observed for the Zn(II) compound with
a Stokes shift of 73 nm.
