@article {46248, title = { Synthesis and reactivity of a hypersilylsilylene }, journal = {Inorganic chemistry}, volume = {58}, year = {2019}, month = {AUG}, pages = {10536-10542}, type = {Article}, abstract = {

Stabilization of an amidinatosilylene with a bulky tris(trimethylsilyl)silyl substituent was realized with the preparation of PhC(NtBu)(2)Si{Si(SiMe3)(3)} (1) from PhC(NtBu)(2)SiHCl2 with K{Si(SiMe3)(3)} in more than 90\% yield. The highly deshielded Si-29 NMR resonance (delta = 76.91 ppm) can be attributed to the absence of a pi-donating substituent. The molecular structure of 1 shows a trigonal-planar geometry around the Si-II center with a Si-II-Si-IV bond length of 2.4339(13) angstrom. A series of reactions of 1 with Me3NO, S, Se, and Te were performed. While siloxane derivatives (2 and 3) are obtained from reactions with Me3NO, silachalcogenones (4-6) are formed with other chalcogens. The presence of Si=E (E = S, Se, and Te) bonds in 4-6 have been confirmed by single crystal X-ray studies. Silaoxirane (7) formation was observed when 1 was treated with acetone, demonstrating the importance of the tris(trimethylsilyl)silyl group to kinetically and thermodynamically protect the silaoxirane derivative with less bulky substituents on the C atom.

}, doi = {10.1021/acs.inorgchem.9b00418}, author = {Bisai, Milan Kumar and Swamy, V. S. V. S. N. and Das, Tamal and Vanka, Kumar and Gonnade, Rajesh G. and Sen, Sakya S.} } @article {47382, title = {Substrate, catalyst, and solvent: the triune nature of multitasking reagents in hydroboration and cyanosilylation}, journal = {Organometallics}, volume = {40}, year = {2021}, month = {APR}, pages = {1104-1112}, type = {Article}, abstract = {

A truly green chemical process would avoid the use of an external catalyst, while still achieving high efficiency. This has been realized in the very recent past for hydroboration, cyanosilylation, acetalization, and the aza-Michael addition, among other reactions. The current combined computational and experimental study unlocks the secret to how this highly desirable outcome is accomplished: one of the reactants in the process also acts as the catalyst. Specifically, this is shown (i) for the important hydroboration reaction, with pinacolborane (HBpin) as the hydroborating reagent and benzaldehyde, acetophenone, benzoic acid and p-methoxyphenylacetylene as the hydroborated substrates, and (ii) for cyanosilylation, with trimethylcyanosilane (TMSCN) as the cyanosilylating agent and benzaldehyde as the substrate. The mechanistic understanding thus gained has then been further exploited experimentally to bring hydroboration and cyanosilylation closer to experimental conditions in catalysis. These insights can potentially be expanded to the rapidly growing area of solvent-free and internal catalyst chemistry.

}, issn = {0276-7333}, doi = {10.1021/acs.organomet.1c00070}, author = {Dixit, Ruchi and Bisai, Milan Kumar and Yadav, Sandeep and Yadav, Vinita and Sen, Sakya S. and Vanka, Kumar} }