CARBON-CARBON BOND-FORMING REACTIONS VIA NEW ORGANOSAMARIUM(III) INTERMEDIATES

New carbon-carbon bond forming reactions via organosamarium(III) intermediates, developed in our laboratory, are reviewed. (Alpha-iminoalkyl)samarium(III) intermediates are generated by treatment of organic halides and 2,6-xylyl isocyanide with samarium(II) iodide. Subsequent reactions with carbonyl compounds produce alpha-hydroxy imines, which are hydrolyzed to the corresponding alpha-hydroxy ketones. Unsymmetrical alpha-diketones are synthesized by autoxidation of alpha-hydroxy imines. The use of 4-(tert-butyldimethylsiloxy)-2,6-xylyl isocyanide in the SMI2-Mediated three-component coupling reaction has led to the stereoselective syntheses of 2-amino alcohols via reduction and subsequent oxidative N-de-arylation. Double insertion of 2,6-xylyl isocyanide into an organic halide mediated by SMI2 provides an efficient synthetic method for hydroxy diketones and vicinal triketones. (Alpha-aminoalkyl)samarium(III), generated through formation of a radical from N-(o-iodobenzyl)amine, its translocation and a subsequent one-electron transfer, is used as a new alpha-amino carbanion equivalent.