112-58-3Relevant articles and documents
Synthesis of the enantiomer of the antidepressant tranylcypromine
Csuk, Rene,Schabel, Magda J.,Von Scholz, Yvonne
, p. 3505 - 3512 (1996)
Both enantiomers of the antidepressant tranylcypromine, trans 2-phenyl-cyclopropylamine 1, were prepared in enantiomerically pure form by a chemoenzymatic approach starting from racemic (±)-(1RS, 2RS)-trans ethyl 2-phenyl-cyclopropane carboxylate (±)-3.
Conversion of 1-hexanol to di-n-hexyl ether on acidic catalysts
Medina, Eduardo,Bringué, Roger,Tejero, Javier,Iborra, Montserrat,Fité, Carles
, p. 41 - 47 (2010)
Conversion, selectivity and yield of 1-hexanol liquid phase dehydration to di-n-hexyl ether (DNHE) were determined at 150-190 °C on three acidic catalysts, the thermally stable resin Amberlyst 70, the perfluoroalkanesulfonic Nafion NR50 and the zeolite H-BEA-25, in a batch reactor. The highest conversion and yield were achieved on Amberlyst 70 at 190 °C, but the most selective catalyst was Nafion NR50. Good results were obtained at 190 °C on the zeolite. Apparent activation energies for the three catalysts were in the range 108-140 kJ/mol. Unlike H-BEA-25, the reaction of DNHE synthesis on Amberlyst 70 and NR50 was a bit more active but less selective than the analogous 1-pentanol dehydration to di-n-pentyl ether (DNPE).
Synthesis of ethyl hexyl ether over acidic ion-exchange resins for cleaner diesel fuel
Guilera,Ramírez,Fité,Tejero,Cunill
, p. 2238 - 2250 (2015)
The synthesis of ethyl hexyl ether as a suitable diesel additive was investigated using 1-hexanol and diethyl carbonate as reactants and acidic ion-exchange resins as catalysts. Liquid-phase experiments were performed in a batch reactor at the temperature range of 403-463 K and 2.5 MPa. The formation of ethyl hexyl ether proceeded from two routes: thermal decomposition of ethyl hexyl carbonate and intermolecular dehydration of 1-hexanol with ethanol. Both pathways require a previous transesterification reaction between diethyl carbonate and 1-hexanol. It was revealed that this reaction is favoured in polymer zones of 0.4 nm nm-3 polymer density (equivalent to 2.6 nm diameter pores in inorganic materials). Acidic ion-exchange resins containing a significant volume fraction of this polymer density are Dowex 50W×2 and Amberlyst 70. By using this kind of catalyst, reaction rate and selectivity are significantly increased. Finally, it was observed that working at low temperature would favour the selectivity to ethyl hexyl carbonate and hinder the undesired formation of alkenes. This journal is
Uranyl(VI) Triflate as Catalyst for the Meerwein-Ponndorf-Verley Reaction
Kobylarski, Marie,Monsigny, Louis,Thuéry, Pierre,Berthet, Jean-Claude,Cantat, Thibault
supporting information, p. 16140 - 16148 (2021/11/01)
Catalytic transformation of oxygenated compounds is challenging in f-element chemistry due to the high oxophilicity of the f-block metals. We report here the first Meerwein-Ponndorf-Verley (MPV) reduction of carbonyl substrates with uranium-based catalysts, in particular from a series of uranyl(VI) compounds where [UO2(OTf)2] (1) displays the greatest efficiency (OTf = trifluoromethanesulfonate). [UO2(OTf)2] reduces a series of aromatic and aliphatic aldehydes and ketones into their corresponding alcohols with moderate to excellent yields, using iPrOH as a solvent and a reductant. The reaction proceeds under mild conditions (80 °C) with an optimized catalytic charge of 2.3 mol % and KOiPr as a cocatalyst. The reduction of aldehydes (1-10 h) is faster than that of ketones (>15 h). NMR investigations clearly evidence the formation of hemiacetal intermediates with aldehydes, while they are not formed with ketones.
Multistep Engineering of Synergistic Catalysts in a Metal-Organic Framework for Tandem C-O Bond Cleavage
Brzezinski, Carter,Chen, Justin S.,Feng, Xuanyu,Lin, Wenbin,Song, Yang,Xu, Ziwan
supporting information, p. 4872 - 4882 (2020/04/01)
Cleavage of strong C-O bonds without breaking C-C/C-H bonds is a key step for catalytic conversion of renewable biomass to hydrocarbon feedstocks. Herein we report multistep sequential engineering of orthogonal Lewis acid and palladium nanoparticle (NP) catalysts in a metal-organic framework (MOF) built from (Al-OH)n secondary building units and a mixture of 2,2′-bipyridine-5,5′-dicarboxylate (dcbpy) and 1,4-benzenediacrylate (pdac) ligands (1) for tandem C-O bond cleavage. Ozonolysis of 1 selectively removed pdac ligands to generate Al2(OH)(OH2) sites, which were subsequently triflated with trimethylsilyl triflate to afford strongly Lewis acidic sites for dehydroalkoxylation. Coordination of Pd(MeCN)2Cl2 to dcbpy ligands followed by in situ reduction produced orthogonal Pd NP sites in 1-OTf-PdNP as the hydrogenation catalyst. The selective and precise transformation of 1 into 1-OTf-PdNP was characterized step by step using powder X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, inductively coupled plasma mass spectrometry, infrared spectroscopy, and X-ray absorption spectroscopy. The hierarchical incorporation of orthogonal Lewis acid and Pd NP active sites endowed 1-OTf-PdNP with outstanding catalytic performance in apparent hydrogenolysis of etheric, alcoholic, and esteric C-O bonds to generate saturated alkanes via a tandem dehydroalkoxylation-hydrogenation process under relatively mild conditions. The reactivity of C-O bonds followed the trend of tertiary carbon > secondary carbon > primary carbon. Control experiments demonstrated the heterogeneous nature and recyclability of 1-OTf-PdNP and its superior catalytic activity over the homogeneous counterparts. Sequential engineering of multiple catalytic sites in MOFs thus presents a unique opportunity to address outstanding challenges in sustainable catalysis.