1432-38-8Relevant articles and documents
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.
Silicon-center chiral silicon-oxygen compound and preparation method thereof
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Paragraph 0106-0108; 0110-0111, (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.
