4542-57-8Relevant articles and documents
Mechanism and kinetics of 1-dodecanol etherification over tungstated zirconia
Rorrer, Julie,He, Ying,Toste, F. Dean,Bell, Alexis T.
, p. 13 - 23 (2017)
Growing interest in finding renewable alternatives to conventional fossil fuels and petroleum-derived specialty chemicals has motivated the investigation of biomass-derived alcohols to make ethers as diesel additives or lubricants. To optimize the direct etherification of long chain alcohols in the liquid phase, it is necessary to develop an understanding of the kinetics and mechanism of etherification and dehydration reactions. In this study, tungstated zirconia was identified as a selective solid-acid catalyst for the liquid-phase etherification of 1-dodecanol. Investigations of the mechanism and kinetics of this reaction suggest that cooperation between Br?nsted- and Lewis-acid sites on tungstated zirconia enhances the selectivity to ether by increasing the surface concentration of adsorbed alcohol, thereby promoting bi-molecular ether formation relative to unimolecular alcohol dehydration. The suggested rate limiting step for etherification is the formation of a C–O bond between two adsorbed alcohol molecules, and the suggested rate-limiting step for dehydration is the cleavage of the C–H bond of the β-carbon atom in an adsorbed alcohol. Measurements of the kinetic isotope effects for etherification and dehydration support the proposed mechanism. A microkinetic model based on the proposed mechanism for dodecanol etherification and dehydration over tungstated zirconia accurately describes the observed effects of alcohol concentration and product inhibition.
An ether compound of green high-efficient synthetic method (by machine translation)
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Paragraph 0058, (2018/07/07)
The invention discloses an ether compound of green high-efficient synthetic method, energy-saving environmental protection, comprising: mild reaction system, uses aldehyde, silane as the starting material, under the action of the silver salt in a price, for in solvent-free conditions, through reducing the - coupling - cheng mi reaction, realization of high efficiency alcohol of preparation. Synthesis method of the invention has the advantages of low dosage of catalyst, solvent-free, conversion and high yield, the reaction time is short, safe and stable, easy to operate, the product only distillation purification without any additional organic solvent, the whole range of green, environmental protection, high efficiency and the like, can overcome the defects of the prior art, it has very good industrial application value. (by machine translation)
Continuous-Flow Multistep Synthesis of Cinnarizine, Cyclizine, and a Buclizine Derivative from Bulk Alcohols
Borukhova, Svetlana,Nol, Timothy,Hessel, Volker
, p. 67 - 74 (2016/01/16)
Cinnarizine, cyclizine, buclizine, and meclizine belong to a family of antihistamines that resemble each other in terms of a 1-diphenylmethylpiperazine moiety. We present the development of a four-step continuous process to generate the final antihistamines from bulk alcohols as the starting compounds. HCl is used to synthesize the intermediate chlorides in a short reaction time and excellent yields. This methodology offers an excellent way to synthesize intermediates to be used in drug synthesis. Inline separation allows the collection of pure products and their immediate consumption in the following steps. Overall isolated yields for cinnarizine, cyclizine, and a buclizine derivative are 82, 94, and 87 %, respectively. The total residence time for the four steps is 90 min with a productivity of 2 mmol h-1. The incredible bulk: Bulk alcohols are converted continuously into chlorides using HCl in a microflow. A reaction network that consists of four steps and two inline separations leads to the continuous preparation of cinnarizine, cyclizine, and a buclizine derivative with yields of 82, 94, and 87 %, respectively. The total residence time for the four steps is 90 min with a productivity of 2 mmol h-1.
