One-dimensional C—H...N hydrogen-bonded polymers in flexible tetra­pyridyl systems

In N,N,N′,N′-tetra­kis(2-pyridyl­methyl)­propane-1,3-diamine, C₂₇H₃₀N₆, (I), and N,N,N′,N′-tetra­kis(2-pyridyl­methyl)­butane-1,4-diamine, C₂₈H₃₂N₆, (II), the twofold rotational symmetry of (I) favours the formation of a one-dimensional hydrogen-bonded polymer with two columns of C—H...N hydrogen bonds, while the inversion symmetry of (II) allows the formation of a one-dimensional hydrogen-bonded polymer stabilized by four columns of C—H...N hydrogen bonds. The possible role played by the chain length of the linking alkanediamine in determining the type of supra­molecular architecture in this series of compounds is discussed.