Synthesis of a Ketorolac Model via Aromatic Carbenoid Insertion

Abstract

AbstractThe decomposition of diazo ester 2b with chiral RhII catalysts proceeded via intramolecular aromatic carbenoid insertion to the racemic pyrrole derivative 5b in 72% yield. In contrast, the benzoylated precursor 16 afforded no ketorolac 1b when exposed to RhII. Methyl 2‐diazo‐4‐phenylbutyrate (19), in turn, reacted, by 1,2‐hydrogen migration rather than by aromatic substitution, to 20.