778-25-6Relevant academic research and scientific papers
Electrochemistry as a correlation tool candidate with catalytic activities in Ru-catalyzed hydrolytic oxidation of organosilane
Na, Youngim,Lee, Chongmok,Pak, Jae Youn,Lee, Kuk Hwa,Chang, Sukbok
, p. 7863 - 7865 (2004)
Electrochemical parameters measured from a series of ruthenium complexes are nicely correlated with both structural changes and catalytic activities of those species under the reaction conditions providing a possibility that electrochemistry may offer a facile tool for better understanding of some transition metal-catalyzed reactions.
Mechanistic Studies on the Hexadecafluorophthalocyanine–Iron-Catalyzed Wacker-Type Oxidation of Olefins to Ketones**
Grinenko, Vadim,Klau?, Hans-Henning,Kn?lker, Hans-Joachim,Puls, Florian,Seewald, Felix
, p. 16776 - 16787 (2021/11/04)
The hexadecafluorophthalocyanine–iron complex FePcF16 was recently shown to convert olefins into ketones in the presence of stoichiometric amounts of triethylsilane in ethanol at room temperature under an oxygen atmosphere. Herein, we describe an extensive mechanistic investigation for the conversion of 2-vinylnaphthalene into 2-acetylnaphthalene as model reaction. A variety of studies including deuterium- and 18O2-labeling experiments, ESI-MS, and 57Fe M?ssbauer spectroscopy were performed to identify the intermediates involved in the catalytic cycle of the oxidation process. Finally, a detailed and well-supported reaction mechanism for the FePcF16-catalyzed Wacker-type oxidation is proposed.
METHOD OF PREPARING SILANOLS WITH SELECTIVE CYTOCHROME P450 VARIANTS AND RELATED COMPOUNDS AND COMPOSITIONS
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Paragraph 00122-00123, (2021/08/27)
This disclosure provides a method of preparing a silanol-functional organosilicon compound with a cytochrome P450 variant that facilitates the oxidization of a silyl hydride group to a silanol group in the presence of oxygen. The method includes combining the cytochrome P450 variant and an organosilicon compound having at least one silicon-bonded hydrogen atom to give a reaction mixture and exposing the reaction mixture to oxygen to oxidize the organosilicon compound, thereby preparing the silanol-functional organosilicon compound. Cytochrome P450 variants suitable for use in the method are also disclosed, along with methods for engineering and optimizing the same. Nucleic acids encoding the cytochrome P450 variants and compositions, expression vectors, and host cells including the same are also disclosed.
Silicon-center chiral silicon-oxygen compound and preparation method thereof
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Paragraph 0106-0109; 0111-0112; 0116, (2021/07/24)
The invention belongs to the field of chiral silicon synthesis, and discloses a silicon-center chiral silicon-oxygen compound. The compound has a structure represented by general formula I shown in the specification. In the formula I, X is Si(R)n or a formula also shown in the specification, R is selected from alkyl, cycloalkyl and aryl, R is selected from alkyl, substituted phenyl and aryl, R is selected from alkyl, phenyl and substituted phenyl, n is 3, the three R are the same or different, R is selected from hydrogen and (C1-C4) alkyl, m is selected from 0, 1, 2 and 3, and Y is selected from substituted phenyl, substituted pyrenyl, aryl, heteroaryl and cycloalkyl. The invention also discloses a preparation method of the compound. Various highly functionalized chiral siloxanes and silyl ethers are obtained with good chemical, regional and stereo control and high yield, the variety of silicon center chiral compounds is expanded, and the method has the advantages of high enantioselectivity, wide substrate application range, mild reaction conditions, atom economy and the like. In addition, the compound provided by the invention has a huge application prospect in chiral organic photoelectric materials.
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.
Metal-free hydrogen evolution cross-coupling enabled by synergistic photoredox and polarity reversal catalysis
Cao, Jilei,Lu, Kanghui,Ma, Lishuang,Yang, Xiaona,Zhou, Rong
supporting information, p. 8988 - 8994 (2021/11/23)
A synergistic combination of photoredox and polarity reversal catalysis enabled a hydrogen evolution cross-coupling of silanes with H2O, alcohols, phenols, and silanols, which afforded the corresponding silanols, monosilyl ethers, and disilyl ethers, respectively, in moderate to excellent yields. The dehydrogenative cross-coupling of Si-H and O-H proceeded smoothly with broad substrate scope and good functional group compatibility in the presence of only an organophotocatalyst 4-CzIPN and a thiol HAT catalyst, without the requirement of any metals, external oxidants and proton reductants, which is distinct from the previously reported photocatalytic hydrogen evolution cross-coupling reactions where a proton reduction cocatalyst such as a cobalt complex is generally required. Mechanistically, a silyl cation intermediate is generated to facilitate the cross-coupling reaction, which therefore represents an unprecedented approach for the generation of silyl cationviavisible-light photoredox catalysis.
Catalytic Enantioselective Dehydrogenative Si-O Coupling to Access Chiroptical Silicon-Stereogenic Siloxanes and Alkoxysilanes
Zhu, Jiefeng,Chen, Shuyou,He, Chuan
supporting information, p. 5301 - 5307 (2021/05/04)
A rhodium-catalyzed enantioselective construction of triorgano-substituted silicon-stereogenic siloxanes and alkoxysilanes is developed. This process undergoes a direct intermolecular dehydrogenative Si-O coupling between dihydrosilanes with silanols or alocohols, giving access to a variety of highly functionalized chiral siloxanes and alkoxysilanes in decent yields with excellent stereocontrol, that significantly expand the chemical space of the silicon-centered chiral molecules. Further utility of this process was illustrated by the construction of CPL-active (circularly polarized luminescence) silicon-stereogenic alkoxysilane small organic molecules. Optically pure bis-alkoxysilane containing two silicon-stereogenic centers and three pyrene groups displayed a remarkable glum value with a high fluorescence quantum efficiency (glum = 0.011, φF = 0.55), which could have great potential application prospects in chiral organic optoelectronic materials.
Photocatalyzed cross-dehydrogenative coupling of silanes with alcohols and water
Lv, Haiping,Laishram, Ronibala Devi,Chen, Jingchao,Khan, Ruhima,Zhu, Yuanbin,Wu, Shiyuan,Zhang, Jianqiang,Liu, Xingyuan,Fan, Baomin
supporting information, p. 3660 - 3663 (2021/04/16)
An efficient method for the dehydrogenative coupling of silanes with alcohols under photocatalysis was developed. The reaction proceeded in the presence of Ru(bpy)3Cl2(0.5 mol%) under visible light irradiation in acetonitrile at room temperature. The developed methodology was also applicable for the synthesis of silanols using water as a coupling partner.
METHOD FOR PRODUCING SILANOLS AND NOVEL SILANOLS
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Paragraph 0053-0054; 0057; 0073-0074, (2021/08/13)
PROBLEM TO BE SOLVED: To provide a method for efficiently producing silanols useful as functional chemicals, and to provide novel silanols. SOLUTION: There is provided a method for producing silanols including a reaction step of reacting alkoxysilanes having Si-OR bonds (R represents a hydrocarbon group having 1 to 6 carbon atoms) with water or heavy water in the presence of a catalyst, wherein a method for producing silanols having an Si-OR' bond (R' represents a hydrogen atom or a deuterium atom) is characterized in that the catalyst is an inorganic solid acid catalyst having a regular pore structure. There is also provided novel silanols obtained thereby. SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
