7153-14-2Relevant articles and documents
One-pot synthesis of 2-alkyl cycloketones on bifunctional Pd/ZrO2 catalyst
Xue, Weiyang,Gu, Bin,Wu, Huiling,Liu, Mengyang,He, Songbo,Li, Jingmei,Rong, Xin,Sun, Chenglin
, (2021/03/26)
2-Alkyl cycloketones are essential chemicals and intermediates for synthetic perfumes and pesticides, which are conventionally produced by multistep process including aldol condensation, separation and hydrogenation. In present work, a batch one-pot cascade approach using aldehydes and cycloketones as the raw materials, and a bifunctional Pd/ZrO2 catalyst was developed for the synthesis of 2-alkyl cycloketones, e.g., cyclohexanone and cycloheptanone. Very high aldehydes (except for paraldehyde with large steric hindrance) conversion and high yields for 2-alkyl cycloketones (e.g., 99 % of conversion for n-butanal and 76 wt.% of yield for 2-butyl cyclohexanone) were obtained at mild temperature of 140 °C. After 10 cycles of reuse, Pd/ZrO2 catalyst showed slight deactivation (ca. 5 % conversion and 10 % yield losses), due to the coke on the catalyst. However, the performance of the catalyst was completely recovered after an oxidative regeneration.
A ε - decalactone with synthetic perfume production method (by machine translation)
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Paragraph 0073; 0074; 0075; 0076; 0077; 0078; 0079; 0080, (2019/05/28)
The invention belongs to the technical field of spice production, and in particular relates to relates to a ε - decalactone with synthetic perfume production method, including: (1) preparing an aqueous alkali; (2) the preparation of cyclohexanone and butyraldehyde mixture A; (3) the alkali is added to the reactor, the footing cyclohexanone is added to the mix in the reactor; (4) is added to the mixture in the reactor A drop, side drop edge added stirring, after dropping to continue stirring, thermal insulation to react to the detected in-butyraldehyde content of 1% until the following; (5) the step (4) and the product and sequentially through the hydrogenation, separation and purification, oxidation, obtained after the separation and purification of the ε - decalactone synthetic perfume; the invention to butyraldehyde and cyclohexanone as the starting material to aldol condensation reaction, and then after hydrogenation of peracetic acid oxidation ring enlargement reaction synthesis ε - decalactone perfume, to excessive cyclohexanone as the reaction solvent, recovery after mechanically, reduce the reaction solvent separation and purification, and raw materials are easy, the reaction yield is high. (by machine translation)
Reversal of enantioselectivity in aldol reaction: New data on proline/λ-alumina organic-inorganic hybrid catalysts
Sz?ll?si, Gyo?rgy,Fekete, Mónika,Gurka, András A.,Bartók, Mihály
, p. 478 - 486 (2014/06/24)
We report new results on the aldol reactions between aldehydes of three different types (aromatic, aliphatic and cycloaliphatic) and acetone/cycloalkanones as reaction partners, driven by organic-inorganic hybrid catalyst Pro/λ-Al2O3. In contrast to the homogeneous liquidphase reaction, over Pro/λ-Al2O 3reversal of the enantioselection in up to 20-40 % ee depending on the structure of the aldehyde was observed in reactions of acetone. Reversal of the ee in the presence of c-Al2O3cannot be generalized, as it has only been observed for acetone among the ketones studied by us. It was proven using methods of a great variety such as ultrasonic irradiation, reuse measurements on used catalyst and the filtrate of the first reaction, measurements on the L-Pro-L-Pro(OH) dipeptide, studies using mixtures of L-Pro and D-Pro that the organic-inorganic hybrid catalyst Pro/λ-Al 2O3formed in situ is responsible for reversal of the ee. In the reactions of cycloalkanones there is presumably competition between the liquid-phase and the surface reaction over Pro/ c-Al2O 3with preference for the former. Based on these results a surface reaction pathway was proposed. Although, the ees obtained under heterogeneous catalytic conditions are low, further studies may lead to application of this unusual phenomenon for obtaining chiral heterogeneous catalysts suitable for the preparation of the desired enantiomer of a chiral compound using the same chiral source. Springer Science+Business Media New York 2013.
