Design And Synthesis Of Methylthio Arylethynes For Application In The Self-Assembly Of Gold Nanoparticles

"Collective phenomena"is one of the most concerned studies of the scientific community. Scale effect is extremely important for the science of complexity and material diversity. Because of the different scales, simple nanoparticle and complex nanoclusters have completely different material properties and movement rule. The methylthio arylethynes we designed have different sizes, geometric shapes and numbers of–SCH3 group. Because different molecules which adhered on the surface of template have different effects on approach quomodo and assembly numbers, which can reach the purpose of adjusting the size and shape of nanoclusters.For the design of target compounds, the first step is to design the terminal functional blocks. According to the one-pot double elimination reaction of methylthio methyl phenyl sulfone with aromatic aldehydes, the blocks of methylthio arylethynes are prepared. In the reaction process, all reagents are added to the system sequently, and the inetermediates do not need separation or post-processing.We design and synthesize four new methylthio arylethynes, which contained two"Y"shaped, one triangle cone shaped and one"V"shaped. They are allπ-conjugated, but the–SR functional groups, geometric shape and size are different. We also discuss some important reactions which included diazotization, electronic substitute, introduction and removal of protecting group, and sonogashira coupling. We focus on researching the synthetic route of target compounds.The structures of the new intermediates and target compounds are confirmed by 1H NMR, 13C NMR, IR, and MS spectra.Finally, we synthesize six reported methylthio arylethynes. They are used as the mediators to participate in the self-assembly of gold nanoparticles. By measuring the spectral evolution of UV-Vis absorption and Surface Plasmon resonance band, the character of nanoclusters, such as assembly rate and optical signal are studied. We also use transmission electron microscope to measure the size of the nanoclusters.