Deoxygenative Nucleophilic Phosphonation and Electrophilic Alkylation of Secondary Amides: A Facile Access to Quaternary α‑Aminophosphonates

The widespread occurrence and synthetic accessibility of amides render them valuable precursors for the synthesis of diverse nitrogen-containing compounds. Herein, we present a metal-free and streamlined synthetic strategy for the synthesis of quaternary α-aminophosphonates. This approach involves sequential deoxygenative nucleophilic phosphonation and versatile electrophilic alkylation of secondary amides in a one-pot fashion. Notably, this method enables the direct bis-functionalization of secondary amides with both nucleophiles and electrophiles for the first time, with simple derivatization leading to valuable free α-aminophosphonates by hydrolysis. The protocol has the advantages of operational simplicity, broad functional-group compatibility, environmental friendliness, and scalability to multigram quantities

Facile Access to Functionalized Spiro[indoline-3,2′-pyrrole]-2,5′-diones via Post-Ugi Domino Buchwald–Hartwig/Michael Reaction

A novel access to spiro­[indoline-3,2′-pyrrole]-2,5′-diones is presented via a palladium-catalyzed post-Ugi cascade cyclization approach involving a Buchwald–Hartwig/Michael reaction sequence. The method allows the easy construction of a library of spirooxindoles in moderate to good yields starting from readily available precursors. In addition, alkynoic acids are replaced with α,β-unsaturated acids leading to variably substituted spirooxindoles

An Expedient Route to Imidazo[1,4]diazepin-7-ones via A Post-Ugi Gold-Catalyzed Heteroannulation

A novel diversity-oriented post-Ugi/gold(I)-catalyzed heteroannulation process for the synthesis of imidazo[1,4]diazepin-7-ones is elaborated. The scope and limitations of the protocol are discussed

Cationic Gold(I)-Catalyzed Cascade Bicyclizations for Divergent Synthesis of (Spiro)polyheterocycles

We herein report an expeditious synthetic strategy to access diverse (spiro)­polyheterocycles from easily available starting materials in two operational steps including an Ugi four-component reaction and a cationic gold­(I)-catalyzed cascade bicyclization. Divergent synthesis of these structurally complex pyrido­[2,1-<i>a</i>]­isoindol-4­(6<i>H</i>)-ones and spiroisoquinoline-pyrrole-3,5′-diones via a cascade nucleophilic cyclization/intramolecular 1,3-migration/1,5-enyne cycloisomerization process and a tandem hydroamination/Michael addition sequence, respectively, was controlled by substituents, where the electronic effect on the migrating groups and steric effect of the secondary amide moieties play crucial roles

Cationic Gold(I)-Catalyzed Cascade Bicyclizations for Divergent Synthesis of (Spiro)polyheterocycles

We herein report an expeditious synthetic strategy to access diverse (spiro)­polyheterocycles from easily available starting materials in two operational steps including an Ugi four-component reaction and a cationic gold­(I)-catalyzed cascade bicyclization. Divergent synthesis of these structurally complex pyrido­[2,1-<i>a</i>]­isoindol-4­(6<i>H</i>)-ones and spiroisoquinoline-pyrrole-3,5′-diones via a cascade nucleophilic cyclization/intramolecular 1,3-migration/1,5-enyne cycloisomerization process and a tandem hydroamination/Michael addition sequence, respectively, was controlled by substituents, where the electronic effect on the migrating groups and steric effect of the secondary amide moieties play crucial roles