A Pd 6 L 8 type coordination driven self-assembly was constructed using a tripodal ligand L (L = N 1 ,N 3 ,N 5trimethyl-N 1 ,N 3 ,N 5 -tris[(pyridin-4-yl)methyl]-1,3,5-benzene tricarboxamide) and palladium nitrate. The self-assembly was fully characterised using one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance spectroscopy, electrospray ionization-mass spectroscopy, thermogravimetric analysis, energy-dispersive X-ray spectroscopy and elemental analysis. Use of high resolution transmission electron microscopy (HR-TEM) analysis confirms the discrete nature of the assembly with a dimension of B2.8 nm, consistent with the density functional theory optimised structure. The assembly acts as an efficient homogeneous catalyst for a copper and phosphine free Sonogashira reaction under mild and aerobic conditions in aqueous medium. The catalyst shows equal efficiency for both electron deficient and electron rich aryl iodides and bromides and is also suitable for use with aliphatic alkynes. The utility of the catalyst as a reusable heterogeneous catalyst in toluene was assessed up to the 3rd cycle without any significant loss of catalytic activity.

A coordination driven Pd2L4 nano-cage heterogeneously catalysed Suzuki–Miyaura coupling and homogeneously catalysed Heck–Mizoroki coupling under aerobic phosphine free conditions without significant loss of activity.

A new self-assembled Td-symmetric cage, Pd6L4, and a square assembly, Pd4L4, were constructed using hydrazide based ligands and cis-blocked palladium(ii). Both act as efficient heterogeneous catalysts for Suzuki–Miyaura coupling.

A supramolecular compound, catena-poly{[Cu2(1,3-μ2-(1a))2(μ2-ter)2(H2O)2]n·(6H2O)n} (1) has been synthesized using (1a) [(1a = N(1),N(3),N(5)-trimethyl-N(1),N(3),N(5)-tris((pyridin-4-yl)methyl)-1,3,5-benzene tricarboxamide] and terephthalate (ter) as the pillaring unit by self-assembly. The terephthalate units are connected by copper(II) ions forming a single strand, while a pair of such strands are then linked by (1a) via two pyridyl terminal arms bound to copper(II) nodes on either side forming a one-dimensional double stranded assembly propagating along the c axis. The compound crystallizes in the Fdd2 space group. The cavity created in the interior of this double strand assembly trap six water molecules and are stabilized by hydrogen bonding with the host. The arrangement of the pair of acyclic water trimers in isolated cavities of (1) is such that it resembles a closed-bracket-like formation. The Hirshfeld surface analysis of (1) reveals the presence of strong intermolecular hydrogen-bonding interactions between one-dimensional ladder-like units and with the water trimer in the host cavity. The copper(II)-containing coordination polymer also acts as an efficient catalyst for the Glaser-Hay homo-coupling reaction.

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