One-pot synthesis of new iso-DPP derivatives from terminal alkynes and isocyanates. Issue 39 (26th September 2019)

• Record Type: Journal Article
• Authors: Guild, Jonathan; Morris, Michael J.; Robertson, Craig C.; Speed, Alexander W.H.
• Is Part Of: Tetrahedron letters. Volume 60:Issue 39(2019)
• Publication Date: 2019-09-26
• Subjects: Acetylide -- Alkyne -- Isocyanate -- Heterocycle; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2019.151079
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Highlights: A new route to novel derivatives of the iso -DPP ring system is reported. By changing the conditions, 5-ylidenepyrrol-2(5 H )-ones can also be accessed. Crystal structures of both heterocycles have been determined. The reagents are cheap and readily available and the process is operationally simple. Abstract: The reaction of phenyl acetylide anion with aryl isocyanates followed by quenching with water is shown to produce pyrrolopyrrole ( iso -DPP) derivatives in addition to the isomeric cyclopentadienone imines previously reported. If the reaction is quenched with dilute HCl, 5-ylidenepyrrol-2(5 H )-ones, formed by a Meyer-Schuster rearrangement, can be isolated instead. A possible mechanism for this reaction is suggested.