Divergence in the PBu3-catalyzed [3+2] annulation of phenacylmalononitriles with allenoates, controlled by the γ-substitution on allenoates, offers a tunable synthesis of multifunctionalized cyclopentene carboxamides and cyclopentenols. An unprecedented formation of...

A Strategy for the β‐selective conjugate addition of α‐fluoro‐β‐ketoamides to allenic esters has been developed via phosphine catalysis. This protocol exhibits a broad substrate scope, and a wide range of compounds bearing fluorinated quaternary carbon center was obtained in good to excellent yields. This protocol allows the use of γ‐substituted allenic esters to furnish the products with exclusive β‐selectivity.

An efficient additive-free three-component access to densely functionalized isoxazolidines using diazo compounds, nitrosoarene, and allenic esters has been uncovered.

An unprecedented Cs2CO3-mediated intramolecular cyclization/rearrangement cascade that transforms α-nitroethylallenic esters to functionalized pyrrolin-2-ones has been uncovered. This reaction provides a new and practical approach for the synthesis of medicinally privileged 5-hydroxy-3-pyrrolin-2-ones under mild conditions. The broad potential of this new method was demonstrated by an efficient Au/Ag-catalyzed heteroarylation of 5-hydroxy-3-pyrrolin-2-ones employing electron-rich heteroarenes to furnish heteroaryl-lactam derivatives.