Microwave-Promoted, Metal- and Catalyst-Free Decarboxylative α,β-Difunctionlization of Secondary α‑Amino Acids via Pseudo-Four-Component Reactions ManjappaKiran B. JhangWei-Fang HuangShin-Yi YangDing-Yah 2014 A microwave-promoted, metal- and catalyst-free decarboxylative α,β-difunctionlization of secondary α-amino acids via a pseudo-four-component coupling of proline, aldehyde, and 1,3-diketone to generate multifunctionalized pyrano­[2,3-<i>b</i>]­pyrrole and pyrrolizinone derivatives is reported.