Rhodium(I)‐Catalyzed Carbonylative Annulation of Iodobenzenes with Strained Olefins and 4‐Octyne in the Presence of Furfural Involving ortho‐C–H Bond Cleavage

Abstract

The rhodium(I)‐catalyzed carbonylative annulation of iodobenzenes with strained olefins in the presence of furfural as a carbonyl source, accompanied by ortho‐C–H bond cleavage, is reported. The use of 4‐octyne in place of strained olefins also leads to the formation of the corresponding inden‐9‐one. The timely release of the carbonyl moiety via the rhodium‐catalyzed decarbonylation of furfural plays a decisive role in this reaction.magnified image

Monomerisation of [Rh2(1,3-Bis-(Diphenylphosphino)-Propane)2(μ2-Cl)2] Detected by Pulsed Gradient Spin Echo Spectroscopy and 31P Nmr Monitoring of Metathesis Experiments

“…18 A solution containing DPPP-I (10 mg) in deuterated tetrahydrofuran (THF) (1 mL) was used for the NMR study. 31 P NMR experiments showed a doublet at δ 31.9 ppm with a J P-Rh of 184 Hz, while 1 H and 13 C NMR spectroscopy indicated the presence of only one kind of species in solution. For a detailed characterisation of [Rh 2 (DPPP) 2 (µ 2 -Cl) 2 ], see ref.…”

“…Neutral dimeric Rh(I) complexes stabilised by diphosphine ligands [Rh 2 (PP) 2 (µ 2 -Cl) 2 ] (PP = diphosphine) have interesting applications, mainly in catalysis. Recent examples include the hydrogenation of prochiral olefins, [1][2][3] the formation of C-C bonds mediated by hydrogen, [4][5][6] the addition of carboxylic acids to alkynes, [7][8][9][10] CO gas-free hydroformylation, [11][12] carbonylations 13 and many others. As suggested by several authors, the reactivity of these complexes should be strongly dependent on a dissociative process, which should generate a monomeric, highly reactive 14-electron complex of the type [Rh(PP)Cl] (Scheme 1).…”

Palladium‐Catalyzed Annulation of Acyl Fluorides with Norbornene via Decarbonylation and CO Reinsertion

“…Furthermore,acatalytic Pauson-Khand-type reaction using aldehydes as the CO source has been developed. [16] These reactions proceed via the generation of am etal-carbonyl speciest hat arises from the decarbonylation of the substrates. Therefore, we suspected that the transformation using acyl fluoride 1b also proceeds via as imilar decarbonylation pathway to give indanone 4.…”

Application of Transition Metal‐Catalyzed Decarbonylation of Aldehydes in the Total Synthesis of Natural Products

“…The removal of carbon monoxide from aldehydes to form hydrocarbons is one of the most important transformations for defunctionalization/deoxygenation of biomass in the synthesis of sustainable building blocks. Furthermore, it represents a safer approach in the utilization of carbon monoxide in organic synthesis [4a–f] . Apart from industry, decarbonylation reaction is widely used in academic research [5] .…”