Hydrogenolysis of the chlorosilanes and silyl triflates (triflate = trifluoromethanesulfonate, OTf -) Me3-nSiX1+n (X = Cl, OTf; n = 0, 1) to hydrosilanes at mild conditions (4 bar H2, room temperature) is reported using low loadings (1 mol-%) of the bifunctional catalyst [Ru(H)2CO(HPNP iPr )] (HPNP iPr = HN(CH2CH2P(iPr)2)2). Endergonic chlorosilane hydrogenolysis can be driven by chloride removal, e.g. with NaBAr F 4 (BAr F 4 -= B(C6H3-3,5-(CF3)2 -). Alternatively, conversion to silyl triflates enables facile hydrogenolysis with NEt3 as base, giving Me3SiH, Me2SiH2 and Me2SiHOTf, respectively, in high yields. An outer-sphere mechanism for silyl triflate hydrogenolysis is supported by DFT computations. These protocols provide key steps for the synthesis of the valuable hydrochlorosilane Me2SiClH, which can also be directly obtained in yields over 50% by hydrogenolysis of chlorosilane/silyl triflate mixtures. catalyzed hydrogenolysis of chlorosilanes and silyl triflates with low catalyst loadings.

Two novel disilenes of type ABSi=SiAB bearing N-heterocyclic imino (A = NItBu) and trialkylsilyl (B = SitBu31, B = SitBu2Me 2) groups are reported. The reduced steric demand in 2 results in a highly stable,...

We report a detailed computational and experimental study of the fixation and reductive coupling of dinitrogen with low-valent boron compounds. Consistent with our mechanistic findings, the selectivity toward nitrogen fixation or coupling can be controlled through either steric bulk or the reaction conditions, allowing for the on-demand synthesis of nitrogen chains. The electronic structure and intriguing magnetic properties of intermediates and products of the reaction of dinitrogen with borylenes are also elucidated using high-level computational approaches.

Trichlorosilane is the key intermediate for the large-scale production of polycrystalline silicon in the Siemens and Union Carbide processes. Both processes, however, are highly inefficient, and over two thirds of the trichlorosilane employed is converted to unwanted silicon tetrachloride accumulating in millions of tons per year on a global scale. In this combined experimental and theoretical study we report an energetically and environmentally benign synthetic protocol for the highly selective conversion of SiCl 4 to HSiCl 3 using organohydridosilanes as recyclable hydrogen transfer reagents in combination with onium chlorides as efficient catalysts. We put the same protocol to further use demonstrating the quantitative conversion of higher oligosilane residues, which form as another unwanted and potentially hazardous byproduct of Siemens processes, to HSiCl 3 in a low-temperature recycling step.