791-31-1Relevant articles and documents
Reactions of carboxamides with vinylsilanes under oxidative conditions
Astakhova, Vera V.,Moskalik, Mikhail Yu.,Shainyan, Bagrat A.
, (2022/01/11)
The reactions of acetamide, benzamide and trifluoroacetamide with trimethyl(vinyl)-, triphenyl(vinyl)-, dimethyl(divinyl)- and diphenyl(divinyl)silanes in the presence of oxidants (t-BuOCl + NaI) or N-bromosuccinimide (NBS) in acetonitrile have been studied. Generally, all unsaturated silanes react with trifluoroacetamide to give the products of haloamidation, whereas with acetamide or benzamide the reaction affords mainly the products of halogenation. The formation of bromoamination product containing the MeCONH moiety in the NBS-induced reaction of trimethylvinylsilane with all studied amides clearly indicates that the reaction proceeds with the solvent (MeCN) interception rather than by the attack of the amide nucleophile. The product of bromoamidation from the NBS-promoted reaction undergoes a base-induced cyclization to the corresponding 1,3-oxazoline in quantitative yield.
Cobalt single atoms anchored on nitrogen-doped porous carbon as an efficient catalyst for oxidation of silanes
Yang, Fan,Liu, Zhihui,Liu, Xiaodong,Feng, Andong,Zhang, Bing,Yang, Wang,Li, Yongfeng
, p. 1026 - 1035 (2021/02/09)
The oxidation reactions of organic compounds are important transformations for the fine and bulk chemical industry. However, they usually involve the use of noble metal catalysts and suffer from toxic or environmental issues. Here, an efficient, environmentally friendly, and atomically dispersed Co catalyst (Co-N-C) was preparedviaa simple, porous MgO template and etching method using 1,10-phenanthroline as C and N sources, and CoCl2·6H2O as the metal source. The obtained Co-N-C catalyst exhibits excellent catalytic performance for the oxidation of silanes with 97% isolated yield of organosilanol under mild conditions (room temperature, H2O as an oxidant, 1.8 h), and good stability with 95% isolated yield after nine consecutive reactions. The turnover frequency (TOF) is as high as 381 h?1, exceeding those of most non-noble metal catalysts and some noble metal catalysts. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), extended X-ray absorption fine structure (EXAFS), and wavelet transform (WT) spectroscopy corroborate the existence of atomically dispersed Co. The coordination numbers of Co affected by the pyrolysis temperature in Co-N-C-700, Co-N-C-800, and Co-N-C-900 are 4.1, 3.6, and 2.2, respectively. Owing to a higher Co-N3content, Co-N-C-800 shows more outstanding catalytic performance than Co-N-C-700 and Co-N-C-800. Moreover, density functional theory (DFT) calculations reveal that the Co-N3structure exhibits more activity compared with Co-N4and Co-N2, which is because the Co atom in Co-N3was bound with both H atom and Si atom, and it induced the longest Si-H bond.
Selective Electrochemical Hydrolysis of Hydrosilanes to Silanols via Anodically Generated Silyl Cations
Liang, Hao,Wang, Lu-Jun,Ji, Yun-Xing,Wang, Han,Zhang, Bo
supporting information, p. 1839 - 1844 (2020/12/01)
The first electrochemical hydrolysis of hydrosilanes to silanols under mild and neutral reaction conditions is reported. The practical protocol employs commercially available and cheap NHPI as a hydrogen-atom transfer (HAT) mediator and operates at room temperature with high selectivity, leading to various valuable silanols in moderate to good yields. Notably, this electrochemical method exhibits a broad substrate scope and high functional-group compatibility, and it is applicable to late-stage functionalization of complex molecules. Preliminary mechanistic studies suggest that the reaction appears to proceed through a nucleophilic substitution reaction of an electrogenerated silyl cation with H2O.