Adhikari Manu, Kumar Thakur Sandeep, Singh Sanjay
Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab, 140306, India.
Chemistry. 2025 Jan 22;31(5):e202403322. doi: 10.1002/chem.202403322. Epub 2024 Nov 21.
Hydride abstraction from the borane adduct, (BICAAC) ⋅ BH afforded the hydride bridged dinuclear borenium ion equivalent complexes 1 and 2 that have been characterized by various spectroscopic and spectrometric techniques followed by the assessment of Lewis acidity using the Gutmann-Beckett method. The single crystal X-ray structure of complex 2 revealed the presence of discrete ions in the solid state. The complex (BICAAC) ⋅ BH(OTf) (3), obtained from the reaction of (BICAAC) ⋅ BH with MeOTf, formed the corresponding boronium cations (BICAAC) ⋅ BH(L) on reaction with Lewis bases (L= pyridine (4) and DMAP (5)). Complexes 1 and 2 demonstrated notable catalytic activity in the hydrosilylation of a diverse array of carbonyls using 1.0 mol % catalyst loading (achieving the highest turnover frequency (TOF) of up to 1200 h with benzaldehyde. A broad substrate scope has been presented for aldehydes and ketones decorated with various electron-donating and withdrawing substituents along with this the hydrosilylation of a few para-quinone methides has also been presented.
从硼烷加合物（BICAAC）·BH中夺取氢化物，得到了氢化物桥连的双核硼正离子等价配合物1和2，它们已通过各种光谱和光谱技术进行了表征，随后使用古特曼-贝克特方法评估了路易斯酸度。配合物2的单晶X射线结构表明在固态中存在离散离子。由（BICAAC）·BH与MeOTf反应得到的配合物（BICAAC）·BH（OTf）（3），在与路易斯碱（L =吡啶（4）和DMAP（5））反应时形成了相应的硼正离子(BICAAC)·BH(L)。配合物1和2在使用1.0 mol%催化剂负载量的多种羰基化合物的硅氢化反应中表现出显著的催化活性（以苯甲醛为例，实现了高达1200 h的最高周转频率（TOF））。本文展示了一系列带有各种供电子和吸电子取代基的醛和酮的广泛底物范围，同时还展示了一些对苯醌甲基化物的硅氢化反应。
