Preparation of E-1,3-diaminoethenyl functional groups by the reaction of enol tosylate of alpha-formylglycine with primary and secondary amines

The E-1,3-diaminoethenyl functional group is a potentially useful synthon. A number of examples of E-1,3-diaminoethenyl functional groups were prepared in good yield starting from an E-enol tosylate of a serine based diketopiperazine and 1°- or 2° amine nucleophiles. The reaction proceeds via a stereoselective nucleophilic substitution pathway.