CARBONYLATION OF NITRO AND AZO-COMPOUNDS IN THE PRESENCE OF IRON CARBONYL CATALYSTS

The reactions of nitro and azo compounds with carbon monoxide were stu died in the presence of iron carbonyl catalysts. It was shown that the se catalytic systems differ substantially from Pd- and Rh-containing c atalysts. In the case of the iron catalysts, the products of coupling of molecules are formed as intermediates and azo compounds are the fin al reaction products. The reactions involving the palladium and rhodiu m catalysts proceed without the intermediate formation of the coupling products and lead to isocyanates or carbamates. When combined using P dCl2 and Fe(CO)(5)/Al2O3, the catalysts inhibit each other, especially in the presence of pyridine.