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Herein, for the first time, we disclose the gold‐catalyzed alkoxy‐carbonylation of aryl and vinyl iodides utilizing ligand‐enabled Au(I)/Au(III) redox catalysis. The present methodology is found to be general, efficient, employs mild reaction conditions and showcases a broad substrate scope even with structurally complex molecules. Density functional theory (DFT) calculations revealed mechanistic pathways distinct from those of conventional transition metal‐catalyzed carbonylation reactions. [ABSTRACT FROM AUTHOR]

Studies on a cycloisomerization reaction of 2‐prenylated‐2H‐pyrans towards cis‐fused tetrahydro‐6H‐benzo[c]chromene systems (reduced cis‐THC analogues) are reported. The transformation is catalyzed by iron chloride and proceeds with the formation of two new bonds and two stereocenters diastereoselectively. The same catalyst also promotes the formation of these products via a one‐pot tandem Knoevenagel condensation of 1,3‐cyclohexanediones and citral or farnesal aldehydes, followed by cycloisomerization establishing a direct assembly of this important scaffold. [ABSTRACT FROM AUTHOR]

An achiral Cp*Co(III)‐catalyzed enantioselective C−H activation/annulation of chiral sulfoximine‐enabled thioamides with ynamides is presented herein. This method successfully synthesizes axially chiral five‐membered 2‐amidoindenones with good enantiocontrol. Interestingly, the annulation with chiral oxazolidone‐containing ynamides could provide a separable mixture of diastereomers (up to ~10 : 1 dr). Moreover, enantiopure sulfoximines could be recovered with ~99 % purity, making this method practical. DFT studies show valuable insight into the mechanism and origin of asymmetric induction. [ABSTRACT FROM AUTHOR]

Decomposition of aryl and unsubstituted diazo ester into Rh(II)‐carbenes by the [(IMes)Rh2(OAc)4] complex is shown to be slower than with Rh2(OAc)4. Diazo esters substituted by a second electron‐withdrawing group do not suffer nitrogen extrusion when exposed for several hours to this (NHC)Rh(II) complex at room temperature. This chemoselective decomposition of diazo esters depending on their substituent (Ar, H, EWG) can furthermore be achieved on a mixture of substrates. The catalytic activity of [(IMes)Rh2(OAc)4] towards electron‐poor diazo compounds is also restored by heating to reflux in chloroform, or after decomplexation of the NHC by addition of GaCl3. The [(IMes)Rh2(OAc)4] complex was then used to induce a fully selective reaction cascade from a mixture of two diazo esters. First, a donor/acceptor diazo compound was decomposed selectively at room temperature to give an intermolecular O−H insertion product without any decomposition of the electron poor diazo compound. Addition of GaGl3 then triggered nitrogen extrusion from the diazo malonate to give a 1,5‐C−H insertion product. This transformation, where decomposition of diazo compounds catalyzed by Rh(II) complexes can be externally controlled, represents the first example of assisted tandem catalysis with two metal carbene precursors. [ABSTRACT FROM AUTHOR]

A tandem three‐component C−H bond addition involving the activation of an inert C(sp3)−H bond is reported. The process enables the direct regioselective synthesis of 1,2‐difunctionalized arenes with the formation of C(sp3)− and C(sp2)−C(arene) bonds. 2‐Iodobenzoic acid derivatives behave as masked bifunctional reagent (BFR) and react with 2‐pyridyl‐methyl sulfoximine (MPyS) protected aliphatic acids bearing α,α‐disubstituted groups, and alkenes to produce β‐aryl‐δ‐alkenyl amide derivatives in a single operation. The transformation involves Pd(II)/Pd(IV) and Pd(II)/Pd(0) catalytic systems. Detailed mechanistic studies, including density functional theory (DFT) calculations, reveal the formation of large T‐shaped palladacycles and the onset of a 1,2‐palladium migration via decarboxylation. [ABSTRACT FROM AUTHOR]