Multiple Pathways in the Self-Assembly Process of a Pd4L8 Coordination Tetrahedron

• Published in: Inorganic chemistry Vol. 57; no. 5; pp. 2686 - 2694
• Main Authors: Tateishi, Tomoki, Kojima, Tatsuo, Hiraoka, Shuichi
• Format: Journal Article
• Language: English
• Published: American Chemical Society 05.03.2018
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.7b03085

The self-assembly of a Pd4 1 8 coordination tetrahedron (Tet) from a ditopic ligand, 1, and palladium­(II) ions, [PdPy*4]2+ (Py* = 3-chloropyridine), was investigated by a 1H NMR-based quantitative approach (quantitative analysis of self-assembly process, QASAP), which allows one to monitor the average composition of the intermediates not observed by NMR spectroscopy. The self-assembly of Tet takes place mainly through three pathways and about half of the Tet structures were produced through the reaction of a kinetically produced Pd3L6 double-walled triangle (DWT) and 200-nm-sized large intermediates (Int L ). In two of the three pathways, the leaving ligand (Py*), which is not a component of Tet, catalytically assisted the self-assembly. Such a multiplicity of the self-assembly process of Tet suggests that molecular self-assembly takes place on an energy landscape like a protein-folding funnel.