In-air structural transformation observed from the synthesis of a new mixed-ligand coordination polymer

A new mixed-ligand coordination polymer, {[Cu(BDC)(Phen)(H2O)] · (H2O)(DMF)}n 1 (BDC = 1,4-benzenedicarboxylate; Phen = 1,10-phenanthroline) has been synthesized and characterized. It was found that the complex 1, crystallized in orthorhombic crystal system, was transformed into a more stable compound due to the evaporation of inclusion solvents in air, {[Cu(BDC)(Phen)(H2O)] 2, and the complex 2 was characterized in triclinic crystal system. Complex 1: space group Pnma with unit cell dimensions a=23.378(2), b=12.830(1) and c=6.984(1) Å, Z=4. Complex 2: space group P1̄ with unit cell dimensions a=9.004(1), b=10.527(1) and c=10.577(1) Å, α=114.779(1), β=92.246(1), γ=114.746(1), Z=2.