Self‐Assembly of Shape‐Persistent Hexagonal Macrocycles with Trimeric Bis(terpyridine)–Fe<sup>II</sup>Connectivity
作者:Sinan Li、Charles N. Moorefield、Pingshan Wang、Carol D. Shreiner、George R. Newkome
DOI:10.1002/ejoc.200800185
日期:2008.7
A novel family of bis(terpyridinyl) ligands was designed and constructed by facile Pd-catalyzed coupling reactions. Subsequent terpyridine–transition-metal complexation facilitated self-assembly resulting in a hexagonal, trimeric series of metallomacrocycles. An enhanced solubility of a macrocycle and its bis(terpyridine) precursor possessing elongated, alkyl-branched phenylacetylene spacers was achieved
Construction of hexanuclear macrocycles by a coupling strategy from polyfunctionalized bis(terpyridines)
作者:Ibrahim Eryazici、George R. Newkome
DOI:10.1039/b811607e
日期:——
The construction of a heteronuclear (Ru4Fe2) hexameric metallomacrocycle with methyl- and carbonyl-functionalized bis(terpyridyl) moieties was achieved by a self-assembly of a dinuclear trimer, which was prepared in high yield viaPd(0) coupling of a bis-iodo functionalized dinuclear complex with a terpyridine possessing an acetylene group.
通过甲基和羰基官能化的双(叔吡啶基)部分的异核(Ru 4 Fe 2)六聚金属大环的构建是通过双核三聚体的自组装实现的,该双核三聚体是通过Pd(0)偶联而高产率制备的。一种双碘官能化的双核配合物,其中的吡啶具有一个乙炔基。
Self-Assembly of Metallo-Supramolecules under Kinetic or Thermodynamic Control: Characterization of Positional Isomers Using Scanning Tunneling Spectroscopy
Coordination-driven self-assembly has been extensively employed to construct a variety of discrete structures as a bottom-up strategy. However, mechanistic understanding regarding whether self-assembly is under kinetic or thermodynamic control is less explored. To date, such mechanistic investigation has been limited to distinct, assembled structures. It still remains a formidable challenge to study the kinetic and thermodynamic behavior of self-assembly systems with multiple assembled isomers due to the lack of characterization methods. Herein, we use a stepwise strategy which combined self-recognition and self-assembly processes to construct giant metallo-supramolecules with 8 positional isomers in solution. With the help of ultrahigh-vacuum, low-temperature scanning tunneling microscopy and scanning tunneling spectroscopy, we were able to unambiguously differentiate 14 isomers on the substrate which correspond to 8 isomers in solution. Through measurement of 162 structures, the experimental probability of each isomer was obtained and compared with the theoretical probability. Such a comparison along with density functional theory (DFT) calculation suggested that although both kinetic and thermodynamic control existed in this self-assembly, the increased experimental probabilities of isomers compared to theoretical probabilities should be attributed to thermodynamic control.