614-14-2Relevant articles and documents
Zirconium-catalyzed cyclopropanation of α-olefins mediated by R′CO2R″ and ClnAlEt3-n
Khafizova, Leila O.,Gubaidullin, Rinat R.,Dzhemilev, Usein M.
, p. 9142 - 9147 (2011)
A Cp2ZrCl2-catalyzed one-pot cyclopropanation method has been developed to afford alkoxycyclopropanes and cyclopropanols from α-olefins involving esters of carboxylic acids and ClnAlEt 3-n.
Ambient-pressure highly active hydrogenation of ketones and aldehydes catalyzed by a metal-ligand bifunctional iridium catalyst under base-free conditions in water
Wang, Rongzhou,Yue, Yuancheng,Qi, Jipeng,Liu, Shiyuan,Song, Ao,Zhuo, Shuping,Xing, Ling-Bao
, p. 1 - 7 (2021/05/17)
A green, efficient, and high active catalytic system for the hydrogenation of ketones and aldehydes to produce corresponding alcohols under atmospheric-pressure H2 gas and ambient temperature conditions was developed by a water-soluble metal–ligand bifunctional catalyst [Cp*Ir(2,2′-bpyO)(OH)][Na] in water without addition of a base. The catalyst exhibited high activity for the hydrogenation of ketones and aldehydes. Furthermore, it was worth noting that many readily reducible or labile functional groups in the same molecule, such as cyan, nitro, and ester groups, remained unchanged. Interestingly, the unsaturated aldehydes can be also selectively hydrogenated to give corresponding unsaturated alcohols with remaining C=C bond in good yields. In addition, this reaction could be extended to gram levels and has a large potential of wide application in future industrial.
Ruthenium-p-cymene Complex Side-Wall Covalently Bonded to Carbon Nanotubes as Efficient Hybrid Transfer Hydrogenation Catalyst
Blanco, Matías,Cembellín, Sara,Agnoli, Stefano,Alemán, José
, p. 5156 - 5165 (2021/11/05)
A half-sandwich ruthenium-p-cymene organometallic complex has been immobilized at Single Walled Carbon Nanotubes (SWNT) sidewalls through a stepwise covalent chemistry protocol. The introduction of amino groups by means of diazonium-chemistry protocols leads the grafting at the outer walls of the nanotubes. This hybrid material is active in the transfer hydrogenation of ketones to yield alcohols, using as hydrogen source 2-propanol. SWNT?NH2?Ru presents a broad scope, performing the reaction under aerobic conditions and can be recycled over 9 consecutive reaction runs without losing activity or leaching ruthenium out. Comparison of the activity with related homogeneous catalysts reveals an improved performance due to the covalent bond between the metal and the material, achieving turnover frequencies as high as 192774 h?1.
Rhodium-Catalyzed Regiodivergent Synthesis of Alkylboronates via Deoxygenative Hydroboration of Aryl Ketones: Mechanism and Origin of Selectivities
Zhang, Bing,Xu, Xin,Tao, Lei,Lin, Zhenyang,Zhao, Wanxiang
, p. 9495 - 9505 (2021/08/04)
Here, we report an efficient rhodium-catalyzed deoxygenative borylation of ketones to synthesize alkylboronates, in which the regioselectivity can be switched by the choice of the ligand. The linear alkylboronates were obtained exclusively in the presence of P(nBu)3, and PPh2Me favored the formation of branched alkylboronates. The protocol also allows access to 1,1,2-triboronates from the readily available ketones. Mechanistic studies suggest that this Rh-catalyzed deoxygenative borylation of ketones goes through an alkene intermediate, which undergoes regiodivergent hydroboration to afford linear and branched alkylboronates. The different steric effects of PPh2Me and P(nBu)3 were found to be responsible for product selectivity by density functional theory calculations. The alkene intermediate can alternatively undergo sequential dehydrogenative borylation and hydroboration to deliver the triboronates.
