Studies on the hydrogenation of cinnamaldehyde over Pd/C catalysts

Abstract

The hydrogenation of cinnamaldehyde was investigated using a 5% Pd/C catalyst in a 250 cm3 stirred tank reactor and 500 cm3 autoclave. The experiments were carried out at 273–343 K and 0·1–1·1 MPa. Non‐polar solvents, e.g. toluene, decane, methylcyclohexane, decalin, ether and heptane, and polar solvents such as methanol, ethanol, propan‐1‐o1, propan‐2‐ol, butan‐1‐ol and butan‐2‐ol were used to study the selectivity with respect to hydrocinnamaldehyde formation, the reaction kinetics and mass transfer. The additives, such as potassium acetate, ferrous chloride, ferrous sulphate and quinoline were incorporated into the catalyst in order to improve the catalyst selectivity, which was observed especially in the case of potassium acetate. © 1998 SCI

Chemoselective Hydrogenation of Cinnamaldehyde over Pd/CeO2–ZrO2 Catalysts

“…Recently hydrocinnamaldehyde was found be an important intermediate in the preparation of pharmaceuticals used in the treatment of HIV [2]. Supported Pt, Ru, Co, Au and Ir catalysts [3][4][5][6][7][8] were reported to selectively hydrogenate the carbonyl group resulting in cinnamyl alcohol. On the contrary, supported Pd catalysts were selective for hydrogenation of olefinic group resulting in hydrocinnamyl aldehyde [9].…”

A hybrid polyketone–SiO2 support for palladium catalysts and their applications in cinnamaldehyde hydrogenation and in 1-phenylethanol oxidation

“…Moreover, no mention of the recyclability of the catalysts was made [22]. A very recent paper reports an interesting comparison of TOF data for CAL hydrogenation employing different Pd supported catalysts (Pd/C, Pd/carbon nanofiber, Pd/carbon nanofiber/TiO 2 , Pd/Al 2 O 3 , Pd/SiO 2 ) in the temperature range of 60-80 • C and pressure range of 0.2-4 MPa of hydrogen, in different solvents [23].…”

“…The Pd/PK-SiO 2 catalysts were tested in two probe reactions: the selective hydrogenation of cinnamaldehyde (CAL) to hydrocinnamaldehyde (HCAL) carried out in decalin and, as a preliminary investigation, in the oxidation of 1-phenylethanol (1-PE) to acetophenone (AcPh) performed in water. The first reaction is a model reaction to investigate the effect of the catalyst morphology on the selectivity [7,9,19,[22][23][24][25][26][27][28] and, in addition, HCAL has recently been found as an important intermediate for the preparation of pharmaceuticals [25].…”

Influence of Preparation Modes on Pt–Ni/CNTs Catalysts Used in the Selective Hydrogenation of Cinnamaldehyde to Hydrocinnamaldehyde

“…Recently, HCMA is found to be an important intermediate in the preparation of pharmaceuticals used in the treatment of HIV [4]. Although various attempts have been made to develop a suitable catalytic system for selective hydrogenation of CMA to HCMA [5][6][7][8], the selectivity is still an important issue, especially under heterogeneous catalysis conditions. Because of the competitive reduction of the aldehyde carbonyl and olefin groups, the selectivity of CMA to HCMA or CMO varies considerably with the method of preparation of the catalyst, the solvent, additives, the process conditions employed and even trace impurities in the reactant [9][10][11][12][13][14].…”