Immobilization of rhodium-based transfer hydrogenation catalysts on mesoporous silica materials was written by Long, Jie;Liu, Guohua;Cheng, Tanyu;Yao, Hui;Qian, Qingqian;Zhuang, Jinglan;Gao, Fei;Li, Hexing. And the article was included in Journal of Catalysis in 2013.Synthetic Route of C9H9NO This article mentions the following:
Rhodium TsDPEN complex was immobilized on mesoporous silica as reusable catalyst for transfer hydrogenation of aryl ketones into chiral benzyl alcs. The immobilization procedure comprised in situ reaction of [Cp*RhCl2]2 with (S,S)-(MeO)3SiCH2CH2C6H4SO2NHCHPhCHPhNH2 (1) followed by hydrolytic chemisorption on mesoporous silica, or cocondensation of (EtO)4Si with 1 followed by reaction of functionalized silica with [Cp*RhCl2]2. A series of chiral heterogeneous rhodium catalysts obtained via immobilization of chiral N-sulfonylated diamine-based organorhodium complexes within mesoporous silicate networks have been obtained through the postgrafting, postmodification, and co-condensation strategies. Structural analyses and characterizations disclose their well-defined single-site rhodium species within materials, while electron microscopy images reveal their highly ordered dimensional-hexagonal mesostructures. By systemically comparing these prepared strategies, it is found that they exhibit obviously different catalytic activities and enantioselectivities in aqueous asym. transfer hydrogenation of aromatic ketones. The direct anchoring of chiral organorhodium complexes onto the outside surface of mesoporous silica can maintain high enantioselectivity, while the co-condensation of chiral organorhodium complexes into the inside surface of mesoporous silica can form a uniform distribution of active rhodium centers. Both strategies show higher catalytic efficiency than the postmodification strategy in enantioselective performance. This outcome from the study clearly demonstrates the nature of these heterogeneous catalysts based on different immobilization strategies and offers a general way to optimize the prepared strategy to adjust the catalytic efficiency of heterogeneous catalysts. In the experiment, the researchers used many compounds, for example, (R)-4-(1-Hydroxyethyl)benzonitrile (cas: 101219-69-6Synthetic Route of C9H9NO).
(R)-4-(1-Hydroxyethyl)benzonitrile (cas: 101219-69-6) belongs to nitriles. Nitrile function is a very important functional group because it can be manipulated to other functional groups such as carboxylic acid by hydrolysis or amine by reduction, respectively. In conventional organic reductions, nitrile is reduced by treatment with lithium aluminium hydride to the amine. Reduction to the imine followed by hydrolysis to the aldehyde takes place in the Stephen aldehyde synthesis, which uses stannous chloride in acid.Synthetic Route of C9H9NO
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts