| Abstract
| - The preparation of d,l-phenylalanine viaamidocarbonylation of benzyl chloride with acetamideand CO/H2 is described. The rate of the reaction isdependent upon the CO pressure below 250bar, but independent of the hydrogen pressure. A reactiontemperature of 100 °C gives optimumyields. A relatively large amount of the catalyst,Co2(CO)8, is needed for completeconversion becauseof inhibition caused by hydrogen chloride which is formed during thereaction. Addition of NaHCO3removes HCl as insoluble NaCl, resulting in improved conversion andselectivity of the reaction.It also allows the use of a stoichiometric amount of acetamide,whereas a 2- to 3-fold excess ofacetamide is needed for complete conversion of benzyl chloride withoutNaHCO3. Amidocarbonylation of benzyl alcohol gave d,l-phenylalanine in only 8%yield.
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