Selective Hydrogenation Of Chloronitrobenzene Or Cinnamaldehyde Over Supported Platinum Catalysts

Haloamine is important intermediates for synthesis of organic fine chemicals, such as dyes, drugs, herbicides and pesticides. Cinnamaldehyde (CMA), a member of α,β-unsaturated aldehydes, and its semi- hydrogenated products such as cinnamyl alcohol(CMO) and hydrocinnamaldehyde (HCMA) are important fine chemicals and intermediates especially in perfume industry and medicine manufacture. Study on the selective hydrogenation of α,β-unsaturated aldehydes is of great importance in potential industrial applications and theoretical aspects. The selective hydrogenation has been attention for its lower impact on the environment. Homogeneous hydrogenation shows higher activity and selectivity, however, it is difficult to separate catalyst from product. From the point of view of green chemistry, the development of industrial processes for direct production of organic intermediates using heterogeneous catalysts is an industrially meaningful target, since the catalysts could be easily removed from the reaction mixtures and wastes could be largely diminished.Hydrogenation of N=O group is easier than hydrogenolysis of the C-Cl bond on the hydrogenation of chloronitrobenzene (CNB). It is easier for the hydrogenation of C=C group than hydrogenation of C=O group on the hydrogenation of CMA. More activated adsorptive hydrogen and more active sites for the hydrogenation of unsaturated bond on catalyst's surface improve catalytic activity and selectivity on the hydrogenation of CNB and CMA. Based on the rule of selective hydrogenation of CNB and CMA, we design a series of catalysts supported by ZrO₂ or TiO₂. They show better hydrogenation properties on the selective hydrogenation of CNB and CMA. The results we obtained are as follows:In chapter 1, we review the results on the selective hydrogenation of CNB and CMA.In chapter 2, hydrogenation properties of CNB have been studied over different support materials of Pt catalyst (such as polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) and ethyl cellulose (EC)) in ethanol at 303K and atmosphere pressure.