A novel three-component reaction catalyzed by dirhodium(II) acetate: decomposition of phenyldiazoacetate with arylamine and imine for highly diastereoselective synthesis of 1,2-diamines.

[reaction: see text] A practical highly diastereoselective synthesis of 1,2-diamines through carbon-carbon bond formation involving an ammonium ylide intermediate is reported for the first time. By treating methyl phenyldiazoacetate with arylamine and imine in the presence of dirhodium acetate, the erythro diastereomer of methyl 1,2-diaryl-1,2-diaminopropanoate is formed with stereochemical preferences greater than 10:1.