Selenium assisted carbonylation with carbon monoxide

Abstract

Selenium reacts with carbon monoxide and amines under mild conditions to give ammonium carbamoselenoates, which were then converted to corresponding ureas by aminolysis upon oxidation with molecular oxygen. Under the controlled conditions, the reaction proceeds with a catalytic amount of selenium, and its turnover number reached ca. 104. Successful applications of this Se/CO system include not only the synthetic reactions of a variety of carbamates, carbonates, and sulfur or selenium containing compounds but also metallurgical refinement of selenium and several important industrial processes as exemplified by isocyanate synthesis, water-gas shift reaction, and separation of carbon monoxide. The basis of these reactions is the facile in situ generation of carbonyl selenide, which possesses a potent reactivity toward a variety of nucleophiles. © 1993 IUPAC