van IJzendoorn Bono, Whittingham Jessica B M, Whitehead George F S, Kaltsoyannis Nikolas, Mehta Meera
Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Dalton Trans. 2023 Oct 3;52(38):13787-13796. doi: 10.1039/d3dt02896h.
Despite p-block clusters being known for over a century, their application as catalysts to mediate organic transformations is underexplored. Here, the boron functionalized [P] cluster [(BBN)P] ([1]; BBN = 9-borabicyclo[3.3.1]nonane) is applied in the dearomatized reduction of pyridines, as well as the hydroboration of imines and nitriles. These transformations afford amine products, which are important precursors to pharmaceuticals, agrochemicals, and polymers. Catalyst [1] has high stability in these reductions: recycling nine times in quinoline hydroboration led to virtually no loss in catalyst performance. The catalyst can also be recycled between two different organic transformations, again with no loss in catalyst competency. The mechanism for pyridine reduction was probed experimentally using variable time normalization analysis, and computationally using density functional theory. This work demonstrates that Zintl clusters can mediate the reduction of nitrogen containing substrates in a transition metal-free manner.
尽管p区簇合物已为人所知超过一个世纪，但它们作为介导有机转化的催化剂的应用仍未得到充分探索。在此，硼官能化的[P]簇合物[(BBN)P]（[1]；BBN = 9-硼双环[3.3.1]壬烷）被应用于吡啶的去芳构化还原以及亚胺和腈的硼氢化反应。这些转化反应生成胺产物，而胺产物是药物、农用化学品和聚合物的重要前体。催化剂[1]在这些还原反应中具有高稳定性：在喹啉硼氢化反应中循环使用九次后，催化剂性能几乎没有损失。该催化剂还可以在两种不同的有机转化反应之间循环使用，同样催化剂活性也没有损失。使用可变时间归一化分析对吡啶还原反应的机理进行了实验探究，并使用密度泛函理论进行了计算研究。这项工作表明，金特尔簇合物可以以无过渡金属的方式介导含氮底物的还原反应。
