Abstract
Solvothermal reactions of LnCl(3)center dot 6H(2)O (Ln = Nd, Eu, Yb) with equimolar amounts of 5,11,17,23-tetralcis[(m-carboxyphenyl)azo]-25,26,27,28-tetrahydroxycalix[4]arene (H4L) at 90 or 140 degrees C gave rise to a set of six lanthanide(III) coordination polymers {[Nd2CIL(HCOO)(DMF)(3)(H2O)]center dot 0.5DMF center dot MeCN center dot 1.5H(2)O}(n) (1), {[Ln(2)CIL(HCOO)-(DMF)]center dot sol}(n) (2: Ln = Eu, sol =0.5MeCN center dot 1.5H(2)O; 3: Ln = Yb, sol = 1.5H(2)O), and {[H3O][LnL(H2O)]center dot DMF center dot MeCN center dot H2O}(n) (4: Ln = Nd; 5: Ln = Eu; 6: Ln = Yb). Complexes 1-6 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Compounds 1-3 have two-dimensional (2D) networks in which [Nd6Cl4L2(DMF)(12)(H2O)(2)] units (1) or [Ln(6)Cl(4)L(2)(DMF)(2)] (Ln = Eu (2), Yb (3)) are interlinked by the carboxyl groups of formates. Compounds 4-6 exhibit 2-fold interpenetrating 2D networks in which each [Ln(4)L(H2O)(4)] "four-flier pinwheel" unit works as a planar eight-connecting node to connect its eight equivalents via four L ligands. The formation of 1-6 provided an interesting insight into the temperature effect on the construction of lanthanide(III)/polycarboxylate coordination polymers under solvothermal conditions.