N-杂环卡宾基半不稳定配体与两个侧重吡唑臂(1,3-双((1 H-吡唑-3-基)甲基)-2,3-二氢-1 H-咪唑的金(III)络合物,LH)被合成。络合物[ L Au(III)Cl 3 ]是在室温下甚至在0℃下催化该反应的促进二氢烷氧基化的极好的催化剂。[ L Au(III)Cl 3 ]是迄今为止报道的炔二醇螺环化最有效的催化剂之一。此外,[ L Au(III)Cl 3 ]催化了分子内和分子间加氢胺化反应,实现了良好的转化率。[ L Au(III)Cl3 ]是一种比金(I)类似物[ L Au(I)Cl]更有效的催化剂。对于二氢烷氧基化反应,探查了存在的弱配位阴离子[BAr F 4 ] -((3,5-三氟甲基)苯基硼酸酯)的量对催化效率的依赖性。单晶的X射线衍射分析表明,金配合物[ L Au(III)Cl 3 ]和[ L Au(I)Cl]的固态结构分别显示了预期的正方形平面和线性配位几何形状。
double hydroalkoxylation of internal alkynes could be achieved using a Grubbs-type ruthenium carbene complex or its modified species to deliver a series of bridged- and spiroacetal derivatives in moderate to good yields. This study represents a new example of nonmetathetic reactions catalyzed by Grubbs-type ruthenium carbene complexes.
Development of tethered dual catalysts: synergy between photo- and transition metal catalysts for enhanced catalysis
作者:Danfeng Wang、Robert Malmberg、Indrek Pernik、Shyamal K. K. Prasad、Max Roemer、Koushik Venkatesan、Timothy W. Schmidt、Sinead T. Keaveney、Barbara A. Messerle
DOI:10.1039/d0sc02703k
日期:——
photocatalysis–transition metal catalysis strategies are extensively reported, the majority of systems feature two separate catalysts, limiting the potential for synergistic interactions between the catalytic centres. In this work we synthesised a series of tethered dual catalysts allowing us to investigate this underexplored area of dual catalysis. In particular, Ir(I) or Ir(III) complexes were tethered
Intramolecular Alkyne Hydroalkoxylation and Hydroamination Catalyzed by Iridium Hydrides
作者:Xingwei Li、Anthony R. Chianese、Tiffany Vogel、Robert H. Crabtree
DOI:10.1021/ol052186i
日期:2005.11.1
[reaction: see text] Iridium(III) hydrides prove to be air-stable active catalysts for intramolecular hydroalkoxylation and hydroamination of internal alkynes with proximate nucleophiles. The cyclization follows highly selective 6-endo-dig regiochemistry when regioselectivity is an issue.
Highly efficient Rh(i) and Ir(i) single and dual metal catalysed dihydroalkoxylation reactions of alkyne diols
作者:Joanne Hui Hui Ho、Richard Hodgson、Jörg Wagler、Barbara Ann Messerle
DOI:10.1039/b926773e
日期:——
A highly efficient rhodium(I) and iridium(I) catalysed dihydroalkoxylation reaction of alkyne diols is employed here for the synthesis of spiroketals and a fused bicyclicketal. The two metal catalysts show differential selectivity and efficiency for either the cyclisation of the 5-exo or 6-endo-membered rings. For the first time, a dual metal (Rh and Ir) catalyst system is effectively utilised for
Enhancements in catalytic reactivity and selectivity of homobimetallic complexes containing heteroditopic ligands
作者:Mark R. D. Gatus、Roy T. McBurney、Mohan Bhadbhade、Barbara A. Messerle
DOI:10.1039/c7dt01294b
日期:——
organometallic group 9 complex, Ir(I) bimetallic complex, 13, to selectively favour the opposite spirocyclisation product from that reported in the literature, 14c vs 14b. The Ir(I) homobimetallic complex catalyses the intramolecular hydroamination reaction of alkynamines efficiently and proved to be a highly active catalyst for promoting the subsequent hydrosilylation of the pyrrolines; completing the hydrosilylation
Rh(I)和Ir(I)同型双金属配合物是在异戊二烯骨架上使用异位配体系统合成的,该骨架上含有单齿N-杂环卡宾配体和双齿双(吡唑-1-基)甲烷配体。测试该络合物作为两步二氢烷氧基化和两步加氢胺化/氢化硅烷化反应的催化剂。这是有机金属9族配合物Ir(I)双金属配合物13的第一个已知报道,其选择性地支持与文献报道的相反的螺环化产物14c vs 14b。Ir(I)同双金属配合物有效地催化炔胺的分子内加氢胺化反应,并被证明是促进随后的吡咯啉氢化硅烷化的高活性催化剂。在不到40秒的时间内完成氢化硅烷化反应。