caa a22 4500 469056975 CHVBK 20180323132846.0 cr unu---uuuuu 170328e19921201xx s 000 0 eng 10.1007/BF03002936 doi (NATIONALLICENCE)springer-10.1007/BF03002936 Hydrodehalogenation of polychlorinated aromatics with Pd/C catalyst under multiphase conditions [Elektronische Daten] [Pietro Tundo, Carlos Marques, Maurizio Selva] Idrodealogenazione catalitica con Pd/C di idrocarburi aromatici policlonirati in un tistema multifasico Polyhalogenated benzenes, when reacted with hydrogen at atmospheric pressure or sodium hypophosphite and in the presence of Pd/C catalyst in a multi-phase system constituted by a hydrocarbon solvent, a strong alkaline aqueous solution and a quaternary onium salt, allow the rapid and progressive replacement of all the chlorine atoms. Thus, operating with hydrogen at 50°C, 1, 2, 4, 5-tetrachlorobenzene yields benzene after 50 min in 99% yield and using a Pd/Cl ratio of 1/120. The presence of an alkaline medium and a phase-transfer agent is synergic. The enhancement of the reaction rate, compared with the already known methods, has been attributed to the enhanced absorption of hydrogen by the catalyst surtace, to partition of halogenated compounds between the hydrocarbon solution and the liquid phase of the phase-transfer agent and to the rapid removal of HC1 absorbed on Pd/C by the alkaline medium. The reaction is effective also with deactivatedP-methoxyaryl halides. Accademia nazionale dei Lincei, 1992 Hydrodehalogenation of aromatics nationallicence Multiphase reduction system nationallicence Pd/C catalyst nationallicence Tundo Pietro Dipartimento di Scienze Ambientali, Università degli Studi di Venezia, Calle Larga Santa Maria, 2137, 30123, Venezia aut Marques Carlos Dipartimento di Scienze Ambientali, Università degli Studi di Venezia, Calle Larga Santa Maria, 2137, 30123, Venezia aut Selva Maurizio Dipartimento di Scienze Ambientali, Università degli Studi di Venezia, Calle Larga Santa Maria, 2137, 30123, Venezia aut Rendiconti Lincei Springer-Verlag 3/4(1992-12-01), 283-294 1120-6349 3:4<283 1992 3 12210 https://doi.org/10.1007/BF03002936 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF03002936 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tundo Pietro Dipartimento di Scienze Ambientali, Università degli Studi di Venezia, Calle Larga Santa Maria, 2137, 30123, Venezia aut NATIONALLICENCE 700 1- Marques Carlos Dipartimento di Scienze Ambientali, Università degli Studi di Venezia, Calle Larga Santa Maria, 2137, 30123, Venezia aut NATIONALLICENCE 700 1- Selva Maurizio Dipartimento di Scienze Ambientali, Università degli Studi di Venezia, Calle Larga Santa Maria, 2137, 30123, Venezia aut NATIONALLICENCE 773 0- Rendiconti Lincei Springer-Verlag 3/4(1992-12-01), 283-294 1120-6349 3:4<283 1992 3 12210 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer