The complex cobalt pyridine2carboxylate Co(Pyca) 2·4H 2O catalyst is found to have a good activity and selectivity for double carbonylation of benzyl chloride to a substituted phenylpyruvic acid, βbenzyl αphenylpyruvic acid, in CaO/CH 3OH/H 2O reaction system. After stirring 10 h in 3.0 MPa and 333 K with the PhCH 2Cl to CaO ratio of 1.33 and catalyst of 5.5 mmol, the yield of the substituted phenylpyruvic acid is 40%, the selectivity is 80%, and the conversion of benzyl chloride is 51%. The substituted phenylpyruvic acid is characterized by IR, NMR, MS and microanalyses. The strong IR bands at 3 453—3 554 cm -1 are assigned to the —COOH , and the sharp bands at 1 706 and 1 729 cm -1 are assigned to the two C=O groups stretch, respectively. In the 13 C NMR spectra, two characteristic strong peaks at δ 1932 and 1592 are assigned to C=O and COOH. The MS spectra shows that the main characteristic peaks are m/z=254(M+), 236, 209, 181(basic peak), 91 and 77. The melting point of the phenylpyruvic acid is 87—89 ℃. Further study of the double carbonylation reaction over this new catalyst system is being carried out.
