766-08-5Relevant articles and documents
Iron-Catalyzed H/D Exchange of Primary Silanes, Secondary Silanes, and Tertiary Siloxanes
Grayson, Matthew N.,Linford-Wood, Thomas G.,Mahon, Mary F.,Webster, Ruth L.
, p. 2979 - 2985 (2022/03/03)
A synthetic study into the catalytic hydrogen/deuterium (H/D) exchange of 1° silanes, 2° silanes, and 3° siloxanes is presented, facilitated by iron-β-diketiminato complexes (1a and 1b). Near-complete H/D exchange is observed for a variety of aryl- and alkyl-containing hydrosilanes and hydrosiloxanes. The reaction tolerates alternative hydride source pinacolborane (HBpin), with quantitative H/D exchange. A synthetic and density functional theory (DFT) investigation suggests that a monomeric iron-deuteride is responsible for the H/D exchange.
PROCESS FOR THE STEPWISE SYNTHESIS OF SILAHYDROCARBONS
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Page/Page column 54; 57, (2021/12/08)
The invention relates to a process for the stepwise synthesis of silahydrocarbons bearing up to four different organyl substituents at the silicon atom, wherein the process includes at least one step a) of producing a bifunctional hydridochlorosilane by a redistribution reaction, selective chlorination of hydridosilanes with an ether/HCI reagent, or by selective chlorination of hydridosilanes with SiCI4, at least one step b) of submitting a bifunctional hydridochloromonosilane to a hydrosilylation reaction, at least one step c) of hydrogenation of a chloromonosilane, and a step d) in which a silahydrocarbon compound is obtained in a hydrosilylation reaction.
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.
Catalytic Reduction of Alkoxysilanes with Borane Using a Metallocene-Type Yttrium Complex
Aoyagi, Keiya,Matsumoto, Kazuhiro,Shimada, Shigeru,Sato, Kazuhiko,Nakajima, Yumiko
supporting information, p. 210 - 212 (2019/02/01)
The catalytic reduction of alkoxysilanes with the borane HBpin (pin = pinacolato) was achieved using a metallocene-type yttrium complex as a catalyst precursor. Mechanistic study supported the pivotal role of the rigid metallocene structure of the catalyst, which bears two bulky n5-C5Me4SiMe3 ligands, in suppressing the coordination of the side product MeOBpin that is generated during the reaction.
Catalytic oxidation of diorganosilanes to 1,1,3,3-tetraorganodisiloxanes with gold nanoparticle assembly at the water-chloroform interface
Shankar, Ravi,Sharma, Asmita,Jangir, Bhawana,Chaudhary, Manchal,Kociok-K?hn, Gabriele
, p. 813 - 819 (2019/01/09)
The formation of the spherical self-assembly of gold nanoparticles (AuNPs) of 200 ± 20 nm size at the water-chloroform interface is achieved by employing the cyclotetrasiloxane [RSCH2CH2SiMeO]4 (R = CH2CH2OH) as the stabilizing ligand. The interfacially stabilized AuNPs act as a versatile catalyst for selective hydrolytic oxidation of only one of the Si-H bonds in secondary organosilanes, RR1SiH2 (R, R1 = alkyl, aryl, and sila-alkyl), to afford the high yield synthesis of 1,1,3,3-tetraorganodisiloxanes, (HRR1Si)2O. The study unravels for the first time the role of the photothermal effect arising from the excitation of the surface plasmon resonance of the AuNPs under visible light irradiation in enhancing the catalytic activity at ambient temperature.
Synthesis of hydrosilanes: Via Lewis-base-catalysed reduction of alkoxy silanes with NaBH4
Aoyagi, Keiya,Ohmori, Yu,Inomata, Koya,Matsumoto, Kazuhiro,Shimada, Shigeru,Sato, Kazuhiko,Nakajima, Yumiko
supporting information, p. 5859 - 5862 (2019/05/27)
Hydrosilanes were synthesized by reduction of alkoxy silanes with BH3 in the presence of hexamethylphosphoric triamide (HMPA) as a Lewis-base catalyst. The reaction was also achieved using an inexpensive and easily handled hydride source NaBH4, which reacted with EtBr as a sacrificial reagent to form BH3in situ.
MANUFACTURING METHOD OF HYDROSILANE
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Paragraph 0037-0038, (2019/07/13)
PROBLEM TO BE SOLVED: To provide a manufacturing method of hydrosilane capable of manufacturing hydrosilane at good efficiency. SOLUTION: Hydrosilane having a structure represented by the following formula (b) can be manufactured at good efficiency by reacting borohydride and hydrocarbon having a halogen atom and 1 to 20 carbon atoms, and/or a metal salt and further reacting the reaction product with alkoxysilane having a structure represented by the following formula (a) in the presence of triamide phosphate. In the formula (a), R represents a hydrocarbon group having 1 to 20 carbon atoms. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
Organometallic Complexes of Bulky, Optically Active, C 3-Symmetric Tris(4 S -isopropyl-5,5-dimethyl-2-oxazolinyl)phenylborate (ToP)
Xu, Songchen,Magoon, Yitzhak,Reinig, Regina R.,Schmidt, Bradley M.,Ellern, Arkady,Sadow, Aaron D.
, p. 3508 - 3519 (2015/08/06)
A bulky, optically active monoanionic scorpionate ligand, tris(4S-isopropyl-5,5-dimethyl-2-oxazolinyl)phenylborate (ToP), is synthesized from the naturally occurring amino acid l-valine as its lithium salt, Li[ToP] (1). That compound is readily converted to the thallium complex Tl[ToP] (2) and to the acid derivative H[ToP] (3). Group 7 tricarbonyl complexes ToPM(CO)3 (M = Mn (4), Re (5)) are synthesized by the reaction of MBr(CO)5 and Li[ToP] and are crystallographically characterized. The νCO bands in their infrared spectra indicate that π back-donation in the rhenium compounds is greater with ToP than with non-methylated tris(4S-isopropyl-2-oxazolinyl)phenylborate (ToP). The reaction of H[ToP] and ZnEt2 gives ToPZnEt (6), while ToPZnCl (7) is synthesized from Li[ToP] and ZnCl2. The reaction of ToPZnCl and KOtBu followed by addition of PhSiH3 provides the zinc hydride complex ToPZnH (8). Compound 8 is the first example of a crystallographically characterized optically active zinc hydride. We tested its catalytic reactivity in the cross-dehydrocoupling of silanes and alcohols, which provided Si-chiral silanes with moderate enantioselectivity (Chemical Equation).
Magnesium-catalyzed hydrosilylation of α,β-unsaturated esters
Lampland, Nicole L.,Pindwal, Aradhana,Neal, Steven R.,Schlauderaff, Shealyn,Ellern, Arkady,Sadow, Aaron D.
, p. 6901 - 6907 (2015/11/23)
ToMMgHB(C6F5)3 (1, ToM = tris(4,4-dimethyl-2-oxazolinyl)phenylborate) catalyzes the 1,4-hydrosilylation of α,β-unsaturated esters. This magnesium hydridoborate compound is synthesized by the reaction of ToMMgMe, PhSiH3, and B(C6F5)3. Unlike the transient ToMMgH formed from the reaction of ToMMgMe and PhSiH3, the borate adduct 1 persists in solution and in the solid state. Crystallographic characterization reveals tripodal coordination of the HB(C6F5)3 moiety to the six-coordinate magnesium center with a ∠Mg-H-B of 141(3)°. The pathway for formation of 1 is proposed to involve the reaction of ToMMgMe and a PhSiH3/B(C6F5)3 adduct because the other possible intermediates, ToMMgH and ToMMgMeB(C6F5)3, react to give an intractable black solid and ToMMgC6F5, respectively. Under catalytic conditions, silyl ketene acetals are isolated in high yield from the addition of hydrosilanes to α,β-unsaturated esters with 1 as the catalyst.
Activation of N-heterocyclic carbenes by {BeH2} and {Be(H)(Me)} fragments
Arrowsmith, Merle,Hill, Michael S.,Kociok-K??hn, Gabriele
, p. 653 - 662 (2015/03/05)
A stable three-coordinate dimethylberyllium species coordinated by the 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) ligand is readily converted to the corresponding methylhydrido derivative through metathetical reaction with phenylsilane. Attempts to synthesize the corresponding molecular dihydrides are, however, unsuccessful and result in ring opening of an IMes ligand through hydride transfer to the donor carbon atom and the consequent formation of a heterocyclic beryllium organoamide. In agreement with previous calculations, we suggest that this process occurs via a Schlenk-type equilibration process and formation of a four-coordinate bis-NHC beryllium dihydride. These species are not observed, however, as the steric pressure exerted by coordination of the two sterically demanding IMes ligands is sufficient to induce hydride transfer. The latter deduction is supported by the observation that a similar ring-opened product, but derived from methyl and hydride transfer, is available through the introduction of a further equivalent of IMes to the isolated beryllium methyl hydride species. In the latter case the ring-opening process is more facile, which we ascribe to the increased steric pressure achieved upon the formation of four-coordinate beryllium. In a further striking reaction under more forcing thermal conditions, the carbene carbon center of an IMes ligand is observed to be completely eliminated with selective formation of a three-coordinate diamidoberyllium species.
