Toward the Rational Design of Lanthanide Coordination Polymers: a New Topological Approach
The implementation of four bidentate building blocks into a highdenticity linker with a flexible spacer leads to a predisposed ligand that allows one to direct the self- assembly of 1D functional coordination polymers. This is illustrated by the assembly under mild conditions of the luminescent metal-organic framework [Tb(Htpabn)]â14H2O¥ (1; H4tpabn ) N,N,N¢,N¢-tetrakis[(6-carboxypyridin-2-yl) methyl]butylenediamine). The X-ray crystal structure shows that the monoprotonated Htpabn binds two equivalent lanthanide ions to form a one-directional staircase chain. The high ligand denticity prevents solvent coordination and leads to a high luminescence quantum yield (Q ) 39%), which is maintained after solvent removal.