The Addition Reaction of Samarium Enolates and 2-Haloenolates Derived from Esters, and Amides to Imines. Totally Stereoselective Synthesis of Enantiopure 3,4-Diamino Esters or Amides

The addition reaction of samarium enolates and 2-haloenolates derived from esters and amides to imines takes place in an efficient manner. A novel protocol to perform the addition reaction of samarium enolates derived from esters or amides to chiral 2-aminoimines, with total stereoselectivity and without racemization, is also reported. The use of samarium enolates in place of other classic metallic enolates (lithium, magnesium, etc.) could be a valuable alternative to obtain enantiopure 3,4-diamino esters or amides, when enolates of low basicity are necessary.