[2+2] macrocyclic Schiff bases of three kinds have been synthesized from chiral 1,4-diamines by use of different methods. Macrocyclic Schiff bases 1a-1c have been selectively obtained based on a non-templated dilution method from chiral 1,4-diamines a-c and dialdehyde DA1, whereas macrocycles 2a-2c have been selectively produced from reaction of diamines a-c and dialdehyde DA2 in the presence of boric acid as templates. Macrocyclic Schiff bases 3a-3c have been afforded in high selectivity from diamines a-c and dialdehyde DA3 by means of sodium-template. All the titled compounds have been confirmed by ^1H NMR and ESI-MS analyses.
A novel dimeric complex [Ru3 (μ3-O)(μ-CH3COO)(CO)]2(μ-dppf)(μ-odppf)(dppf = 1, 1'-bis(diphenylphosphio)ferrocene, odppf = 1, 1'-bis(oxodiphenylphosphoranyl)ferrocene) (1) of oxo-centered triruthenium-aectate cluster units was synthesized and characterized by X-ray crystallography. Compound 1 exhibits a cyclic structure formed by linkages of two triruthenium cluster units Ru3 (μ3-O)(μ-CH3COO)6(CO) through dppf and odppf ligands, respectively. The diameter of the molecular loop is ca. 1.0 nm.
Nanoscale platinum wires have been prepared by means of an electrochemical technique on DNA template.The platinum nanowires were characterized via transmission electron microscopy(TEM) and X-ray diffraction(XRD).The length of the nanowires was about 50 nm and the diameter was about 1.3 μm.It was found that the concentration of PtCl4,activation time,electrolytic potential and reducing time affected the sizes and shapes of the platinum nanowires.