The new tridentate thioether ligands PhSi(CH2SMe)3 (1) and Ph-p-C6H4Si(CH2SMe)3 (2) have been synthesised and used for the preparation of the chelates fac-[W(κ3-1)(CO)3] and fac-[W(κ3-2)(CO)3], which were characterised by single-crystal X-ray diffraction. 1 and 2 were used as tripodal adsorbate molecules for the fabrication of self-assembled monolayers (SAMs) on gold. Film formation from solution was investigated in situ by second harmonic generation (SHG) and ellipsometry, which revealed a two-stepped process (fast adsorption, followed by slow film ordering). SAMs of 2 on gold were further investigated by ex situ methods, viz. high-resolution X-ray photoelectron spectroscopy (HRXPS), Fourier transform infrared reflection absorption spectroscopy (FTIRRAS), and scanning tunneling microscopy (STM). The latter two methods indicated dense packing of the tripodal anchor groups on the surface, with a substantially lower density of the biphenyl pricks. HRXPS showed three different binding states of sulfur, including a standard thiolate-type and a coordination-type state.
Copper(II)-mediated σ-metathesis with prochiral dihydrosilanes has been successfully leveraged to efficiently synthesize Si-chiral silanols as well as many other related Si-chiral skeletons. The reaction hinges on the continuous generation of catalytically active copper(II) species via single-electron transfer oxidation of copper(I) by alkyl halides and the efficient stereocontrol with multidentate
铜 (II) 介导的σ复分解与前手性二氢硅烷已成功用于有效合成 Si-手性硅烷醇以及许多其他相关的 Si-手性骨架。该反应取决于通过卤代烷对铜 (I) 进行单电子转移氧化连续生成具有催化活性的铜 (II),以及使用多齿阴离子 N,N,P-配体进行有效的立体控制。