Allosteric deprogramming of a trinuclear heterometalli helicate

作者：Riis Johannessen T; Harding Lindsay P; Jeffery John C; Moon Ryan; Rice Craig R^*

来源：Dalton Transactions, 2007, (16): 1577-1587.

DOI：10.1039/b700539c

Two multidentate ditopic ligands L(1) and L(2) which contain both N-donor and crown ether units have been synthesised. The potentially octadentate ligand L(1) forms a trinuclear heterometallic double helicate with Cu(I) and Zn(II) ([Zn(2)Cu(L(1))(2)](5+)), whereas L(2) forms a tetranuclear heterometallic double helicate with the same metal ions ([Zn(2)Cu(2)(L(2))(2)](6+)). Both species have been characterised by (1)H NMR, ESI-MS and single crystal X-ray crystallography. Reaction of [Zn(2)Cu(2)(L(2))(2)](6+) with Ba(2+) results in the coordination of the crown ether units giving the simple barium coordinated species [Zn(2)Cu(2)(L(2))(2)Ba(2)](10+). However, reaction of [Zn(2)Cu(L(1))(2)](5+) with Ba(2+) deprograms the ligand and results in the formation of a mixture of species.

• 出版日期2007