Conformation Dependence of Photophysical Properties of σ–π Conjugation as Demonstrated by<i>cis</i>- and<i>trans</i>-1,2-Diaryl-1,2-disilacyclohexane Cyclic Systems
photophysical properties, such as UV absorption, magnetic circulardichroism (MCD), and photoluminescence. As has been well established, the UV absorption maximum ( 1 L a band) occurs at 230-270 nm, due to the effective σ-π conjugation between the aryl groups and the disilane moiety. The absorption maximum wavelength of the transisomer is slightly longer than that of the cisisomer for all the diaryldisilanes
Diverse Alkyl–Silyl Cross-Coupling via Homolysis of Unactivated C(sp<sup>3</sup>)–O Bonds with the Cooperation of Gold Nanoparticles and Amphoteric Zirconium Oxides
the degradation of polyesters and the synthesis of organosilanes were realized concurrently by the unique catalysis of supported gold nanoparticles. Mechanistic studies corroborated the notion that the generation of alkyl radicals is involved in C(sp3)–Si coupling and the cooperation of gold and an acid–base pair on ZrO2 is responsible for the homolysis of stable C(sp3)–O bonds. The high reusability and
Harnessing Supported Gold Nanoparticle as a Single‐Electron Transfer Catalyst for Decarboxylative Cross‐Coupling
作者:Hiroki Miura、Kaede Ameyama、Tetsuya Shishido
DOI:10.1002/adsc.202300462
日期:2024.1.9
of a stable C(sp3)−O bond took place in the presence of a supported Au NPs catalyst, which realized radical alkyl-silyl cross-coupling to give alkylsilanes (Scheme 1).45, 46 Single-electron oxidation of disilane triggered the fragmentation of a Si−Si bond to furnish highly reactive silyl radicals,47 implying that supported Au NPs function as heterogeneous single-electron transfer catalysts without light
介绍 负载型金纳米颗粒 (Au NPs) 在多种化学反应中表现出优异的催化活性,例如低温下一氧化碳1-4和氨5-7的氧化以及水煤气变换反应。8-14它们的特性还使得有机分子能够进行非均相还原和氧化转化以获得精细化学品。15-25同时,主要基于电子顺磁共振(EPR)光谱的详细研究揭示了金纳米颗粒与有机自由基之间的谐波相互作用。26-33这些发现使我们重新考虑 Au NP 影响下的几种催化有机转化是否可能包括单电子转移。另一方面,过渡金属、光激发金属配合物和无机半导体促进的单电子转移是产生有机自由基的最有力的工具之一。特别是,光氧化还原催化下自由基交叉偶联反应的最新进展使化学家能够合成多样化且复杂的分子。34-44最近,我们发现在负载型 Au NPs 催化剂存在下,稳定的 C( sp 3 )−O 键发生均裂,实现自由基烷基-甲硅烷基交叉偶联,得到烷基硅烷(方案 1)。45, 46乙硅烷的单电子氧化引发了
Rahman, Noorsaadah Abd.; Fleming, Ian; Zwicky, Anna B., Journal of Chemical Research, Miniprint, 1992, # 9, p. 2401 - 2408
作者:Rahman, Noorsaadah Abd.、Fleming, Ian、Zwicky, Anna B.