α,β-Diketo nitriles as dielectrophiles. Formation of heterocyclic derivatives of amino acids

The reactions of mono Boc-protected amino monocarboxylic acids with phosphoranylideneacetonitrile yield ylido nitriles which on ozonolysis at low temperature form labile α,β-diketo nitriles. These derivatives may be used in situ for reaction with diamines or related dinucleophiles to yield hetero derivatives of interest as unnatural amino acid building blocks.