Benzenedicarboxylate Coordination Polymers

Substituent Effect on the Structures OF Zinc 1,4-Benzenedicarboxylate Coordination Polymers Synthesized IN Dimethyl Sulfoxide... 

The coordination polymer [Zn(tmbdc)(dmso)2]-2(DMSO) (tmbdc = 2,3,5,6-tetramethyl-l,4-benzenedicarboxylate) has been synthesized by layer diffusion in DMSO (dimethyl sulfoxide) solution. The compound contains ID chain formed by octahedraly coordinated Zn ion chelated by the carboxyl groups of tmbdc. In another recently reported coordination polymer [Zn2(bdc)2(dmso)2]-5(DMSO) (bdc = 1,4-... 

In order to explore the substituent effect on the assembly of coordination polymers, the influence of other factors should be excluded. Therefore the same synthetic condition as that for 1 was applied to synthesize the zinc 2,3,5,6-tetramethyl-1,4-benzenedicarboxylate, [Zn(tmbdc)(dmso)2] 2(DMSO) 2, except that H2bdc was replaced by H2tmbdc. [20]... 

In conclusion, ID coordination polymer [Zn(tmbdc)(dmso)2]-2(DMSO) 2 has been synthesized with 2,3,5,6-tetramethyl-l,4-benzenedicarboxylic acid in DMSO. The structure contains ID chains formed by octahedraly coordinated Zn ions chelated by the carboxyl groups of tmbdc, rather than the 2D (4,4) nets constructed from paddle-wheel SBU of pairs Zn ions as found in [Zn2(bdc)2(dmso)2]-5DMSO 1. Analysis of the structure reveals that the steric hindrance of die four methyl groups of tmbdc determines the coordination environments of the zinc ions and the coordination modes of the carboxyls, and thus the final structures of the coordination polymers. The result also shows that DMSO is a stronger ancillary ligand and is also easier to be included in the structures of coordination polymers, compared to DMF. DMSO can be a better solvent for the syntheses of porous coordination polymers. 

Octahedral coordination polymers remain much less common that their diamondoid counterparts, but a recent report revealed a novel metal-organic coordination polymer, Zn40(BDC)3 (BDC = benzenedicarboxylate) that suggests an exciting future for such compounds.26 Zn40(BDC)3 is a relatively simple and inexpensive... 

In addition to the regular octahedral cluster core structure, there exists a rare example of an open, chair-like hexanuclear lanthanide hydroxide motif (Figure 6.39) in the hydrother-mally synthesized coordination polymers [Ln3((jL3-0H)2(BDC)3,5(H20)2] H20 (Ln = Y, Yb, Er BDC = 1,4-benzenedicarboxylate) [25,76]. The hexanuclear building block, consisting of six lanthanide ions and four p,3-OH groups, can be conveniently described as four edge-sharing units of [Ln3( X3-OH)]. 

The hydrothermal synthesis of the hexanuclear core-based hydroxido-lanthanide coordination polymers, [R3(BDC)3 5(0H)2(H20)2] H20 (R = Y, Yb, and Er BDC = 1,4-benzenedicarboxylate) further attests the rmiqueness of hydrothermal procedures (Weng et al., 2006). The controlled hydrolysis of lanthanide ions led to an open hexanuclear cluster core, drastically different from the commonly observed cubane or octahedral-shaped cluster cores. The hexanuclear core contains six /i3-OH-bridged R(III) ions from two asymmetric imits and adopts a chair-like configuration (R = Y, Figure 102). This hexanuclear building block is linked by the BDC ligands to form a 3D framework. 

Coordination polymers with 1,4-benzenedicarboxylate (bdc), [Cu2(bdc>2] and [Zu2(bdc)2(H20)2] 2DMF,34 have been reported as robust PCPs, which can retain the channels without guest molecules. These coordination polymers have two-dimensional structmes, in which the dimetal units are connected by bdc. The channels of their compounds show permanent porosity, and N2 molecules adsorption onto these... 

Yang X-P, Jones RA, Rivers JH et al (2007) Syntheses, structures and luminescent properties of new lanthanide-based coordination polymers based rat 1,4-benzenedicarboxylate (bdc). Dalton Trans 35 3936... 

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