Synthesis and reactions of an open‐chain bis‐reissert salt analog

Abstract

An open‐chain bis‐Reissert salt analog 5 has been synthesized and fully characterized. The reaction of the salt analog with methyl acrylate yields the pyrrole 7 which exists in solution in the azafulvene form 7a. The reaction of the salt analog with dimethylacetylene dicarboxylate (DMAD) affords the bispyrrole 9.

Synthesis of bis‐pyrrole tetra esters and alcohols as novel mimetics of the anticancer mitomycin

“…Substituted pyrroles have also been synthesized from aminonitriles, the precursors of amino acids, via the corresponding Reissert compounds [13] as shown by extensive studies by McEwen et al . Thus, for example, the acid‐catalyzed conversion of the Reissert compounds to the corresponding tetrafluoroborate [14] perchlorate [15, 16], trifluoromethane sulfonate [17], and trifluoroacetate salts [18] is well known. These salts exist in a variety of tautomeric structures including diene‐ and meso‐ionic forms that react with alkenes and alkynes to yield highly functionalized heterocyclic compounds.…”

“…Thus, the double Strecker reaction of an aldehyde, potassium cyanide, and diamine followed by the Schotten–Baumann acylation of the resultant bis‐aminonitriles 7 gave the corresponding open‐chain bis‐Reissert compounds 1 [15]. Treatment of bis‐Reissert compounds with acid generated the corresponding bis‐oxazolium salts 8 .…”