Pd together with CuI has been well known as the catalyst towards Sonogashirareaction, which provides an effective route to functional alkynes. However, the achievement of high activity and selectivity of this catalytic system is still challenging in some cases. Illustrative examples include their low activity for aryl chloride substrates, and switched selectivity to oxidative coupling products in
Pd 与 CuI 一起作为 Sonogashira 反应的催化剂是众所周知的,这为功能性炔烃提供了有效的途径。然而,在某些情况下,实现该催化体系的高活性和选择性仍然具有挑战性。说明性的例子包括它们对芳基氯底物的低活性,以及在空气气氛中对氧化偶联产物的选择性转换。在这项工作中,掺入了 Cu 的 Au 13纳米团簇 [Au 13 Cu 2 (PPh 3 ) 6 (SC 2 H 4 Ph) 6 ] + [NO 3 ] - (Au 13 Cu 2) 是通过快速合成以高产率设计和制备的。这种原子级精确的纳米团簇显示出成为 Sonogashira 反应的新型催化系统的潜力,具有高活性和选择性,以及即使在空气中也具有良好的可回收性。
Fused Selenazolinium Salt Derivatives with a Se-N<sup>+</sup>Bond: Preparation and Properties
Convenient methods for the preparation of stable, fused selenazolinium salt systems with a Se–N+ bond have been developed. The mechanism for the formation of the selenazole cycle was investigated in detail by conducting multinuclear NMR experiments. The ability of these compounds to form stable inner salts was demonstrated. We have shown the glutathione peroxidase (GPx) like properties of selenazolopyridinium
已经开发了用于制备稳定的、具有 Se-N+ 键的稠合硒唑啉盐体系的便捷方法。通过进行多核核磁共振实验,详细研究了硒唑循环的形成机制。证明了这些化合物形成稳定内盐的能力。我们已经通过氧化含硫的天然氨基酸以及芳香醛和杂芳香醛,展示了硒唑并吡啶鎓盐的类似谷胱甘肽过氧化物酶 (GPx) 的特性。大多数化合物的分子结构已通过 X 射线衍射研究证实。
Synthesis of highly substituted allylic alcohols by a regio- and stereo-defined CuCl-mediated carbometallation reaction of 3-aryl-substituted secondary propargylic alcohols with Grignard reagents
作者:Xiaobing Zhang、Zhan Lu、Chunling Fu、Shengming Ma
DOI:10.1039/b903769a
日期:——
A highly regio- and stereoselective CuCl-mediated carbometallation reaction of 3-aryl-substituted secondary propargylicalcohols with alkyl, aryl, vinyl or allyl Grignard reagents for the synthesis of fully-substituted allylic alcohols was developed. The R2group from the Grignard reagent was successfully introduced to the 2-position of the propargylicalcohols due to the chelation of metal atom with
An approach for the synthesis of quinolizinone with potential bioactivity has been developed via palladium-catalytic dearomative cyclocarbonylation of allylalcohol. Diverse quinolizinone compounds could be attained with good efficiencies. A feasible reaction pathway could be a successive procedure of allylation, dearomatization, CO insertion and the Heck reaction.
Organocopper reagents smoothly react with heterocyclic propargyl mesylates at low temperature to produce Mused heterocycles. The copper reagent plays a "double duty" in this novel cascade transformation, which proceeds via an S(N)2' substitution followed by a subsequent cycloisomerization step.