A Conceptual Approach to the Synthesis of Bifunctional EDTA Analogs: EDTA-Extended Polyamides

Article abstract of DOI:10.1021/jo00096a025

A conceptual approach to the synthesis of ε-carboxyl and ε-amino polyamide-linked EDTAs is proposed (Scheme 1), starting from ε-carboxy vicinal diamine blocked by Cbz or Boc groups (A, Scheme 1), followed by extension along the chain to form polyamides with ε-carboxy groups (A2, A3,..., An) or amine groups (B1, B2,..., Bn).The An series can be converted to acidic EDTAs (AEn series) or basic EDTAs (BEn series).This depends on the selection of the protecting groups to offer exclusive protection of the amine and acid functions.The choice of the protecting groups (three categories a-c in Scheme 1) provides an exclusive synthetic methodology.This is further exploited for conversion of acidic polyamide-linked EDTA (AEn) to either acidic or basic EDTA homologs (see Scheme 2).Scheme 4 proposes metnodology for synthesis of terminally blocked bis-EDTA polyamides.