| Abstract |
The facile aqueous medium reactions of copper(II) nitrate with BES biobuffer [(HOCH2CH2)(2)N(CH2CH2SO3H), hereinafter referred as H(3)bes] in the presence of various benzenecarboxylic acids [benzoic (Hba), 3-hydroxybenzoic (Hhba), and 3,5-dihydroxybenzoic (Hdhba) acid] and lithium hydroxide gave rise to the self-assembly generation of three new heterometallic Cu-II/Li materials, [Li(H2O)(4)][Cu-4(mu(2)-Hbes)(4)(mu(2)-ba)]center dot H2O (1) and [Cu-4(mu(3)-Hbes)(4)(L)\Li(H2O)(2)\](n)center dot 3nH(2)O \L = mu(2)-hba (2) and mu(2)-dhba (3)\. They were isolated as air-stable crystalline solids and fully characterized by infrared (IR) and UV-vis spectroscopy and electrospray ionization (ESI)-MS(+), elemental, thermal, and single-crystal X-ray diffraction analyses. The latter revealed that 1-3 have comparable packing patterns and unit cell parameters, being composed of similar [Cu-4(mu-Hbes)(4)(mu-carboxylate)](-) cores and [Li(H2O)(4)](+) cations (in 1) or [mu-Li(H2O)(2)](+) groups (in 2 and 3), which are arranged into discrete 0D aggregates in 1 or infinite 3D noninterpenetrating metal-organic networks in 2 and 3. The topological analysis of the coordination polymers 2 and 3 disclosed the trinodal 3,3,4-connected underlying nets with an unprecedented topology defined by the point symbol of (4.6.8)(4)(4(2).6)(2)(6(2).16(2).18(2)), further simplification of which resulted in the binodal 4,4-connected nets with the pts (PtS) topology. Apart from representing very rare examples of coordination compounds derived from H(3)bes, 1-3 feature solubility in water and were applied as efficient and versatile catalyst precursors for the mild (60 degrees C) single-pot hydrocarboxylation, by CO and H2O, of various gaseous, linear, and cyclic C-n (n = 2-9) alkanes into the corresponding Cn+1 carboxylic acids, in H2O/MeCN medium under homogeneous conditions and in the presence of potassium peroxodisulfate. Total yields (based on alkane) of carboxylic acids up to 78\% were achieved, which are remarkable in the field of alkane functionalization under mild conditions, especially for a C-C bond formation reaction in aqueous acid-solvent-free medium. |
