pH Effects on reaction rates in rhodium catalysed hydrogenation in water

Towards catalytic cascade reactions: asymmetric synthesis using combined chemo-enzymatic catalysts

“…Apparently, the activity of 5-AlTUD-1 in this system is still inhibited, despite the absence of phosphate buffer or free enzyme. An explanation for these results is suggested by the report of Malmstro¨m et al [35], who demonstrated that the rates of rhodium-catalysed hydrogenations of 2-acetamidoacrylic acid are strongly dependent on the pH of the mixture. They showed that the steepest change occurred between pH of 4.5 and 3.2, which coincides with the pK a -value of 2-acetamidoacrylic acid.…”

A One‐Pot Enantioselective Chemo‐Enzymatic Synthesis of Amino Acids in Water

“…Apparently the activity of 1-AlTUD-1 in this system is still inhibited, despite the absence of phosphate buffer or free enzyme. An explanation for these results is suggested by the report of Malmstrçm et al, [17] who demonstrated that the rates of the rhodium-catalysed hydrogenation of 2-acetamidoacrylic acid are strongly dependent on the pH of the mixture. They showed that the steepest change occurred between pH of 4.5 and 3.2, which coincides with the pK a value of 2-acetamidoacrylic acid.…”

Developments and Applications of Supported Liquid Phase Catalysts

“…Andersson et al used macromolecular ligands in which TPP moieties were bound to a water soluble polymer, polyacrylic acid or poly-ethyleneimine, for the preparation of Rhbased SLPC [33]. These authors applied those SLPC samples for liquid phase hydroformylation of 1-octene in toluene and continuous gas phase hydroformylation of propene.…”

“…Some previous workers used SLPC in continuous flow reactors for hydroformylation [18,33,40,43,48,66], allylic substitution [37], and oxidation [67]. When support materials are granular, gas-SLPC and liquid-SLPC reactions are possible with fixed-bed reactors and fluidized-bed slurry reactors, similar to conventional solid catalysts.…”