Catalytic α-Allylation of Enones with Alcohols via [Gold(I)]-Mediated [3,3]-Sigmatropic Rearrangement of Propargylic Carboxylates

Diversity-Oriented Synthesis of Indole-Fused Polycyclic Scaffolds via Rhodium-Catalyzed NH-Indole-Directed C-H Coupling of 2-Phenyl-1H-indoles with Propargylic Alcohol Derivatives

Diversity-oriented synthesis strategy for the efficient assembly of indole-fused polycyclic scaffolds via rhodium-catalyzed NH-indole-directed C-H coupling with propargylic alcohol derivatives in a regioselective manner was developed. Five 2-phenyl-1H-indole-embedded core skeletons were synthesized. In particular, three different indole-fused exo-olefin-containing polycycles were realized, which may be manipulated for further chemistry.

Three Component syn-1,2-Arylmethylation of Internal Alkynes

A Pd-catalyzed three-component syn-1,2-arylmethylation of internal alkynes (ynamides/yne-acetates/alkynes) is described. The readily available and bench stable coupling partners iodo-arenes, and methyl boronic acid are successfully used in this coupling strategy to access the methyl-containing tetra-substituted olefins; the scope is broad showing excellent functional-group tolerance. Notably, the transformation is regio- as well as stereoselective. The biologically relevant motifs (BRM) bearing iodo-arenes and ynamides are also used for the late-stage syn-1,2-arylmethylation of alkynes. Aryl-alkylation, aryl-trideuteriomethylation, alkynyl-methylation, and alkenyl-methylation of ynamides are also presented. The Me-substituted alkenes are further transformed into synthetically important β-amino-indenones and α-fluoro-α'-methyl ketones.

Site-selective synthesis of 1,3-dioxin-3-ones via a gold(i) catalyzed cascade reaction

A novel gold(i)-catalyzed protocol for the synthesis of 4H-1,3-dioxin-3-ones is presented.

Direct Synthesis of α-Iodoenones by IPy2BF4-Promoted Rearrangement of Propargylic Esters

A direct access to α-iodoeones from iodonium ion and propargylic tosylates or acetates is described. Bis(pyridine) iodonium tetrafluoroborate (IPy₂BF₄, Barluenga's reagent) promotes the rearrangement of these propargylic alcohol derivatives in mild conditions. The transformation gives β-unsubstituted, β-monosubstituted, and β,β-disubstituted α-iodoenones in high yields. β-Substituted α-iodoenones are obtained with excellent ( Z)-selectivity.

Au(i)/Ag(i) co-operative catalysis: interception of Ag-bound carbocations with α-gold(i) enals in the imino-alkyne cyclizations with N-allenamides

A co-operative Au/Ag catalyst system has been developed to utilize N-allenamides as nucleophilic enal equivalents for the interceptive capturing of incipient carbocations generated through π-acid-triggered imino-alkyne cyclization.