Simple and competitive catalytic hydrogenation of nitrobenzene, allyl benzyl ether and benzyl crotyl ether in alkaline alcoholic media

摘要: Abstract The catalytic hydrogenation of nitrobenzene into aniline, in ethanolic solutions modified by different additions KOH, was studied. Platinum catalysts supported on graphite were used. In solutions, dimer reaction intermediates (azoxybenzene, azobenzene, hydrazobenzene), strongly adsorbed the catalyst, formed thus inducing a decrease selectivity aniline. best aniline obtained neutral or slightly alkaline solution. competitive with benzylic ethers (allyl benzyl ether: C6H5–CH2–O–CH2–CHCH2 and crotyl C6H5–CH2–O–CH2–CHCH–CH3) also studied same experimental conditions, as function acidity solution (obtained addition KOH H2SO4). an acid group CC more easily hydrogenated than NO2 whereas opposite result obtained. rate lower that allyl became equal to zero strong solutions. This can be explained steric effect and/or electronic donor methyl group.