Ga<sup>+</sup>-catalyzed hydrosilylation? About the surprising system Ga<sup>+</sup>/HSiR<sub>3</sub>/olefin, proof of oxidation with subvalent Ga<sup>+</sup> and silylium catalysis with perfluoroalkoxyaluminate anions
作者:Antoine Barthélemy、Kim Glootz、Harald Scherer、Annaleah Hanske、Ingo Krossing
DOI:10.1039/d1sc05331k
日期:——
Already 1 mol% of subvalent [Ga(PhF)2]+[pf]− ([pf]− = [Al(ORF)4]−, RF = C(CF3)3) initiates the hydrosilylation of olefinic double bonds under mild conditions. Reactions with HSiMe3 and HSiEt3 as substrates efficiently yield anti-Markovnikov and anti-addition products, while bulkier substrates such as HSiiPr3 are less reactive. Investigating the underlying mechanism by gas chromatography and STEM analysis
已经有 1 mol% 的亚价 [Ga(PhF) 2 ] + [ pf ] − ([ pf ] − = [Al(OR F ) 4 ] − , R F = C(CF 3 ) 3 ) 引发烯双氢硅烷化温和条件下的债券。以HSiMe 3和HSiEt 3作为底物的反应有效地产生抗马可夫尼科夫和反加成产物,而较大的底物如HSi i Pr 3的反应性较低。通过气相色谱和STEM分析研究其潜在机制,我们意外地发现H 2和金属Ga 0形成。在不添加烯烃的情况下,观察到形成 R 3 Si–F–Al(OR F ) 3 (R = 烷基),这是在小硅离子存在下[ pf ] -阴离子的典型降解产物。电化学分析表明, E 1/2 (Ga + /Ga 0 ; o DFB) = +0.26–的弱配位、极性邻二氟苯中的一价 [Ga(PhF) 2 ] + [ pf ] −具有令人惊讶的高氧化电位。 0.37 V vs. Fc +