By choosing a suitable metal center, ligand, and solvents, we have revealed several structural transformations involving a polymer precursor. (1)(infinity)[Co(bpdc)(H2O)(2)].H2O (1) was prepared by reaction of Na(2)bpdc and Co(NO3)(2) in aqueous solution. Immersing 1 in pyridine/water solutions of (2:1) and (8:1) ratios yielded a second one-dimensional structure (1)(infinity)[Co(bpdc)(py)(2)(H2O)(2)]. 2py (2) and a two-dimensional structure (2)(infinity)[Co(bpdc)(py)(2)].H2O (3), respectively. After heating 1 under N-2 to remove all water within the structure, the compound Co(bpdc) (I-R) was obtained. When In was immersed in solutions of pyridine/water (5:4) and in pure pyridine tin air), a third one-dimensional structure of (1)(infinity)[Co(bpdc)(py)(2)(H2O)(2)]. 2py .H2O (4) and 3, respectively, were-obtained. Compounds 2-4 easily transformed to 1 when immersed in water. Crystal data for 1: monoclinic, space group C2/c with a = 6.950(1), b = 31.585(6), and c = 6.226(1) Angstrom, beta = 95.84(3)degrees, Z = 4. Crystal data for 2: triclinic, space group P (1) over bar with a 9.646(2), b = 10.352(2), and c 17.031(3) Angstrom, a = 79.02(3)degrees, beta = 86.88(3)degrees, gamma = 77.16(3)degrees, Z = 2. Crystal data for 3: triclinic, space group P (1) over bar with a = 9.137(2), b = 10.480(2), and c = 12.254(2) Angstrom, alpha = 102.10(3)degrees, beta = 100.80(3)degrees, gamma = 99.43(3)degrees, Z = 2. Crystal data for 4: orthorhombic, space group Pbcn with a = 13.468(3), b = 16.652(3), and c = 14.977(3) Angstrom, Z = 4.