One-Step Ruthenium-Catalysed Transformation of 1,7-Enynes into Strained Bicyclic Amino Esters

The reaction of 1,7-enynes, synthesised from alpha-amino acids, carried out with diazo compounds in the presence of the Cp*RuCl(cod) catalyst allowed the one-step preparation of various strained bicyclic pipecolic acid derivatives in good yields under mild conditions. The stereoselectivity of the created double bond depends on the nature of the diazoalkane, and the diastereoselectivity arises essentially from steric factors.