135067-91-3Relevant academic research and scientific papers
Distinct Catalytic Performance of Dirhodium(II) Complexes with ortho-Metalated DPPP in Dehydrosilylation of Styrene Derivatives with Alkoxysilanes
Lu, Wenkui,Wu, Xiaoyu,Xie, Xiaomin,Yang, Liqun,Zhang, Zhaoguo,Zhu, Xiaoyu
, p. 10190 - 10197 (2021/08/24)
Herein, we describe dirhodium(II) complexes for the ortho-metalated 1,3-bis(diphenylphosphino)propane (DPPP)-catalyzed dehydrosilylation of vinylarenes with tertiary silanes, particularly alkoxysilanes. This catalytic method displays a broad substrate scope. Both electron-donating and electron-withdrawing substituents on the vinylarenes are well tolerated in this protocol. The dehydrosilylation reactions are compatible with a diverse range of tertiary silanes such as (EtO)3SiH, (TMSO)2MeSiH, (HSiMe2)2O, Et3SiH, and Ph3SiH. Mechanistic studies indicated that a mixture of Rh2(OAc)4, DPPP, and P(OMe)3 provided a stable and rigid dirhodium(II) complex with ortho-metalated DPPP as the bridging ligand and the phosphonate as the axial ligand in the catalytic system. The structure of the dirhodium(II) complexes was also supported by X-ray crystal diffraction. Further experiments confirmed that the dirhodium(II) complexes may be the active species that catalyze the dehydrosilylation reaction. Control experiments showed that norbornene works as the hydrogen acceptor in the reaction and plays a crucial role in the generation of the key catalytic intermediate, a rhodium silicon species.
Additive-modulated switchable reaction pathway in the addition of alkynes with organosilanes catalyzed by supported Pd nanoparticles: Hydrosilylation: versus semihydrogenation
Duan, Yanan,Ji, Guijie,Zhang, Shaochun,Chen, Xiufang,Yang, Yong
, p. 1039 - 1050 (2018/03/05)
We herein report supported Pd nanoparticles on N,O-doped hierarchical porous carbon as a single operation catalyst-enabled additive-modulated reaction pathway for alkynes addition with organosilanes between hydrosilyation and semihydrogenation. In the case of alkynes hydrosilylation, a simple iodide ion as an additive has a promotion effect on the activity and regio- and stereoselectivity, where iodide can coordinate with Pd NPs via strong δ donation to increase the electron density of the Pd atom, resulting in an increased ability for the oxidative addition of hydrosilane as the rate-determining step to make the reaction proceed efficiently to afford vinylsilanes in high yields with excellent regio- and stereoselectivity. For the catalytic transfer semihydrogenation of alkynes, water was introduced to mix with organosilane to form a silanol together with the generation of hydrogen atoms on the Pd NPs surface or the liberation of H2 gas as a reducing agent, whereby the quantitative reduction of alkynes was achieved with exclusive selectivity to alkenes. In both cases, the catalyst could be recycled several times without a significant loss in activity or selectivity. A broad range of alkyl and aryl alkynes with various functional groups are compatible with the reaction conditions. The role the additive exerted in each reaction was extensively investigated through control experiments as well as the kinetic isotopic effect along with spectroscopic characterization. In addition, the respective mechanism operating in both reactions was proposed.
Catalytic Behavior of Rhodium(I) Complexes in Hydrogermylation and Hydrosilylation of Phenylacetylene
Wada, Fumio,Abe, Seiji,Yonemaru, Norio,Kikukawa, Kiyoshi,Matsuda, Tsutomu
, p. 1701 - 1703 (2007/10/02)
Rhodium complexes, Rh(L)(C2H4)2 , catalyze hydrogermylation and hydrosilylation of phenylacetylene with Bu3GeH and R3SiH (R=Bu, Et), respectively, to produce Ph(R3M)C=CH2 (M=Ge, Si) selectively.Other rhodium complexes, that is 2, Rh2Cl2(cod)2, Rh(tmhd)(C2H4)2 , and Rh(dbm)(C2H4)2 , also catalyze these reactions, but with less regioselectivity.
