504-20-1Relevant articles and documents
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King,Lionetti
, p. 2248 (1945)
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Clibbens,Francis
, p. 2358 (1912)
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Improved synthesis method of isophorone
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Paragraph 0042; 0044; 0046-0047; 0049-0050; 0052-0053; ..., (2021/09/08)
The improved isophorone synthesis method comprises the following steps: selecting 2, 2, 6 and 6 - tetramethyl -4 - piperidone to prepare 1 -nitroso 2, 2, 6 and 6 - tetramethyl -4 - piperidone in a market. The large-site alkali-resistant catalyst is potassium isopropoxide. Any one of sodium isopropoxide, potassium tert-butoxide, sodium tert-butoxide, potassium n-butoxide, sodium n-butoxide, potassium isobutanol, sodium isobutanol, potassium n-pentanol, and sodium isoamyl alcohol. To the method, by adopting a large sterically hindered base as a catalyst, the reaction is improved, a large amount of impurities are avoided, the main content is improved from 50% to 90%, the yield is improved from 44% to 80% . the full-process operation is simple and controllable, the cost is low, and industrial production is easy to realize.
In-situ IR Spectroscopy Study of Reactions of C3 Oxygenates on Heteroatom (Sn, Mo, and W) doped BEA Zeolites and the Effect of Co-adsorbed Water
Najmi, Sean,So, Jungseob,Stavitski, Eli,McDermott, William P.,Lyu, Yimeng,Burt, Sam P.,Hermans, Ive,Sholl, David S.,Sievers, Carsten
, p. 445 - 458 (2020/12/01)
The reactions of acetone and hydroxyacetone over heteroatom doped BEA zeolites (Sn, Mo, and W) in the presence and absence of H2O vapor are investigated using infrared spectroscopy. Acetone is converted to mesityl oxide over Sn-BEA exclusively. At higher temperatures, larger oxygenates such as phorones, aromatics, and coke form. The presence of co-adsorbed water in Sn-BEA suppresses tautomerization. H2O vapor is also beneficial for minimizing coke formation at high temperatures. Hydroxyacetone is converted into 2-hydroxypropanal over Sn-BEA, exhibiting high affinity to Sn sites up to 400 °C. Sn-BEA catalyzes conversion of hydroxyacetone into the enol in the absence of H2O, but exposure to H2O induces the formation of 2-hydroxypropanal and subsequent conversion to acrolein. The Lewis acid descriptors are used to rationalize the reaction pathways. For the isomerization of hydroxyacetone into 2-hydroxypropanal, the hardness of acid sites influences the reaction and correlates with the overall Lewis acidity of the catalysts, respectively. However, the size of the exchanged metal significantly affects aldol condensation, where keto and enol forms of acetone adsorb to active sites simultaneously.