Postsynthetic Exchanges of the Pillaring Ligand in Three-Dimensional Metal–Organic Frameworks

Metal–organic frameworks, [Ni(HBTC)(dabco)] (2) and [Ni2(HBTC)2(bipy)0.6(dabco)1.4] (3) (where H3BTC is 1,3,5-benzenetricarboxylic acid, dabco is 1,4-diazabicyclo[2.2.2]octane, and bipy is 4,4′-bipyridine), were prepared via postsynthetic ligand exchanges of [Ni(HBTC)(bipy)] (1). By controlling the concentration of dabco, we could obtain not only entropically favorable 2 with completely exchanged dabco but also enthalpically favorable 3 with selectively exchanged bipy/dabco in the alternating layers.