Rhodium catalyzed carbonylation and related reactions of nitrogen-, sulfur- and oxygen-containing cyclic and acyclic compounds.

Abstract

A systematic investigation has been carried out on the rhodium(I) catalyzed carbonylation of heterocyclic and acyclic compounds containing two heteroatoms at the 1,3-positions. The regioselectivities of carbon monoxide insertion are different in cyclic and acyclic compounds. When there is a choice between C-S and C-N bonds, in acyclic compounds, carbonylation of the C-N bond is more facile and the C-S bond is more easily carbonylated in acyclic compounds. When there is a possibility of ring or side chain carbonylation, it appears that the C-X bond of the side chain is more reactive. Rhodium(I) was also used to catalyze the carbonylation reaction of the N-O bond of isoxazolidine derivatives. When Ir-complexes were used as catalysts, the carbonylation occured and was followed by hydrogen transfer affording tetrahydro-1,3-oxazines as the final products. It was also found that substituents on the isoxazolidines have a dramatic effect on the reactivity of these substrates.