Tri-metal secondary building units: Toward the design of thermally robust crystalline coordination polymers

Three new crystalline coordination polymers [Mn-3(TDC)(4)(H2O)(4)](2,6-lutidine)(2)(H2O)(3) 1, P-1, a = 11.351(3), b = 11.391(3), c = 11.480(3), alpha= 112.838(4), beta= 90.696(4), gamma= 99.328(4); [Zn-3(1,4-BDC)(3)(EtOH)(2)] 2, C2/c, a = 19.1308(9), b = 10.6088(5), c = 16.2221(7), beta= 108.79(1); and [Zn-3(1,3-BDC)(3)(py)(2)](MeOH) 3, P2(1)/c, a = 17.142(3), b = 21.544(4), c = 11.805(2), beta= 106.441(3); TDC = 2,5-thiophenedicarboxylate, BDC = benzedicarboxylate, have been synthesized by linking tri-metal nodes with poly-carboxylate ligands. Single crystal x-ray analysis shows that 1 is composed of (4,4) 2-D grids with A-A stacking while 2 is comprised of (6,3) triangular networks in an A-B-C stacking pattern and 3 has formed a distorted cubic diamondoid topology. Tri-metal nodes are located at the vertexes of each network. Thermal gravimetric analysis demonstrates that 1 and 2 are thermally robust structures with network decomposition temperatures of 375 degrees C and 460 degrees C respectively.