Cyclic Diaryliodonium Research Articles

Synthesis of Tellurium-Containing π-Extended Aromatics with Room-Temperature Phosphorescence.

A synthesis of tellurium-embedded π-extended aromatics from tellurium powder and readily available cyclic diaryliodonium salts has been developed. The versatility of this method has been demonstrated by the synthesis of various functionalized dibenzotellurophenes (DBTe's), a ladder-type π-system, and a heterosumanene. These compounds demonstrated good air/moisture stability and high thermal stability. Remarkably, many DBTe's exhibited interesting tunable room-temperature phosphorescence (RTP) in the solid state.

Enantioselective Ring-Opening/Oxidative Phosphorylation and P-Transfer Reaction of Cyclic Diaryliodoniums

A Cu-catalyzed enantioselective ring-opening/oxidative phosphorylation reaction of cyclic diaryliodonium salts and diarylphosphine oxides in the presence of TEMPO was reported. 18O-Labeled experime...

Two-in-One Strategy for the Pd(II)-Catalyzed Tandem C-H Arylation/Decarboxylative Annulation Involved with Cyclic Diaryliodonium Salts.

We report here a two-in-one strategy for the Pd(II)-catalyzed tandem C-H arylation/decarboxylative annulation between readily available cyclic diaryliodonium salts and benzoic acids. The carboxylic acid functionality can be used as both a directing group for the ortho-C-H arylation and the reactive group for the tandem decarboxylative annulation. By a step-economical double cross-coupling annulation procedure, the privileged triphenylene frameworks were efficiently constructed, which have potential applications in material chemistry.

Annulative π-Extension of Unactivated Benzene Derivatives through Nondirected C-H Arylation.

Annulative π-extension chemistry provides a concise synthetic route to polycyclic arenes. Herein, we disclose a nondirected annulation approach of unactivated simple arenes. The palladium-catalyzed 2-fold C-H arylation event facilitates tandem C-C linkage relays to furnish fully benzenoid triphenylene frameworks using cyclic diaryliodonium salts. The inseparable regioisomeric mixture of 1- and 2-methyltriphenylenes is identified by the combined analysis of ion mobility-mass spectrometry, gas-phase infrared spectroscopy, and molecular simulation studies.

Copper-Catalyzed Enantioselective Ring-Opening of Cyclic Diaryliodoniums and O-Alkylhydroxylamines.

A preparation of 2-hydroxyamino-2'-iodobiaryls via the Cu-catalyzed enantioselective ring-opening reaction of cyclic diaryliodonium salts with O-alkylhydroxylamines is reported. 3,5-Di(tert-butyl)phenyl bis(oxazoline) was found to be the optimal ligand, and up to 99% ee values were achieved. The use of CaO as the base dramatically improved the yields and inhibited the side reactions. Finally, synthetic applications of these hydroxylamines were briefly demonstrated.

Axially Chiral Biaryl Compounds via Cu-Catalyzed Acyloxylations of Cyclic Diaryliodonium Salts

Axially Chiral Biaryl Compounds via Cu-Catalyzed Acyloxylations of Cyclic Diaryliodonium Salts

Synthesis of Bridged Biaryl Atropisomers via Sequential Cu- and Pd-Catalyzed Asymmetric Ring Opening and Cyclization.

Bridged biaryl atropisomers are important units in bioactive molecules. A synthesis of lactone-bridged biaryl atropisomers was realized by a Cu-catalyzed asymmetric ring-opening/acyoxylation of cyclic diaryliodoniums, followed by a palladium-catalyzed diastereoselective cyclization. It was found that a catalytic amount of Cu(OTf)2 served as an additive to promote the palladium-catalyzed Heck cyclization.

Enantioselective Synthesis of Axially Chiral Biaryls via Cu-Catalyzed Acyloxylation of Cyclic Diaryliodonium Salts

We report here a Cu-catalyzed enantioselective acyloxylation of cyclic diaryliodonium salts. With readily available cyclic diaryliodonium salts and ubiquitous aliphatic or (hetero)aromatic carboxyl...

Synthesis of Atropisomers by Ring-Opening of Cyclic Diaryliodonium

Synthesis of Atropisomers by Ring-Opening of Cyclic Diaryliodonium

Synthesis of Dibenzofurans from Cyclic Diaryliodonium Triflates and Water via Oxygen-Iodine Exchange Approach.

An efficient synthesis of a variety of dibenzofuran derivatives via Cu-catalyzed cyclization diaryliodonium salts in water is achieved. Various dibenzofuran derivatives could be obtained in good to excellent yields via this oxygen–iodine exchange approach. A concise synthesis of organic semiconducting material molecule has been achieved using this method.

Cu-Catalyzed Enantioselective Atropisomer Synthesis via Thiolative Ring Opening of Five-Membered Cyclic Diaryliodoniums.

A Cu-catalyzed asymmetric thiolative ring opening reaction of five-membered diaryliodonium salts and potassium thioates for the synthesis of atropisomeric 2'-iodo-[1,1'-biphenyl]-2-yl thioates was realized. The optimal catalytic system, Cu(CH3CN)4PF6/(Ph)-bis(oxazoline), showed the best performance with respect to both yields and stereocontrol. Finally, the utility of these products was briefly demonstrated by the synthesis of an axially chiral P,S-ligand.

Copper‐Catalyzed Asymmetric Ring‐Opening of Cyclic Diaryliodonium with Benzylic and Aliphatic Amines

AbstractA Cu‐catalyzed asymmetric ring‐opening reaction between cyclic diaryliodonium and benzylic or aliphatic amines has been developed. At low concentration of the amines, realized by either mixing the amines with Lewis acid or slow addition of the amines, the reaction afforded the products in high enantioselectivity.magnified image

Cu-Catalyzed Enantioselective Ring Opening of Cyclic Diaryliodoniums toward the Synthesis of Chiral Diarylmethanes.

A Cu-catalyzed enantioselective desymmetrizing ring-opening reaction of six-membered cyclic diaryliodonium salts with carboxylic acids or thioacids is reported for the facile access to chiral diarylmethanes. A Cu/[cyclopropyl bis(oxazoline)] catalyst well discriminates two C-I bonds of prochiral cyclic diaryliodonium salts. A stereochemical model was proposed to rationalize the stereochemical outcome on the basis of the crystal structure of cyclic diaryliodonium salt.

One-pot Annulation for Biaryl-fused Monocarba-closo-dodecaborate through Aromatic B-H Bond Disconnection.

We have developed a one-pot annulation reaction of monocarba-closo-dodecaborate with cyclic diaryliodonium salts to afford biaryl-fused derivatives. Aryl functionalities are introduced at both the 1-carbon and unreactive ortho-boron vertices of the "σ-aromatic" carborane cage without the need for pre-functionalization. DFT calculations revealed that the palladium-catalyzed C-B bond-formation step in this process proceeds through a concerted metalation-deprotonation (CMD)-type pathway for the B-H bond disconnection on the aromatic cage, though such bonds are generally regarded as hydridic.

Synthesis of Functionalized Triphenylenes via a Traceless Directing Group Strategy.

A novel ligand-free Pd-catalyzed cascade reaction between o-chlorobenzoic acids and cyclic diaryliodonium salts is reported. This one-pot procedure involves a carboxylic acid directed o-arylation followed by intramolecular decarboxylative annulation affording various valuable triphenylenes, which can be further transformed into diversified building blocks for material chemistry. For the first time, it was shown that an aromatic halide can react with diaryliodonium salts under the direction of carboxylic acid functionality. It was also demonstrated that the carboxylic acid could be employed as both a traceless directing group and functional handle for the atom- and step-economical one-pot double cross-coupling annulation reaction with cyclic diaryliodonium salts as the π-extending agents.

Iodine(III) Derivatives as Halogen Bonding Organocatalysts.

Hypervalent iodine(III) derivatives are known as versatile reagents in organic synthesis, but there is only one previous report on their use as Lewis acidic organocatalysts. Herein, we present first strong indications for the crucial role of halogen bonding in this kind of catalyses. To this end, the solvolysis of benzhydryl chloride and the Diels-Alder reaction of cyclopentadiene with methyl vinyl ketone served as benchmark reactions for halide abstraction and the activation of neutral compounds. Iodolium compounds (cyclic diaryl iodonium species) were used as activators or catalysts, and we were able to markedly reduce or completely switch off their activity by sterically blocking one or two of their electrophilic axes. Compared with previously established bidentate cationic halogen bond donors, the monodentate organoiodine derivatives used herein are at least similarly active (in the Diels-Alder reaction) or even decidedly more active (in benzhydryl chloride solvolysis).

Enhanced Reactivity by Torsional Strain of Cyclic Diaryliodonium in Cu-Catalyzed Enantioselective Ring-Opening Reaction

Summary Atropisomers are stereoisomers arising from the restricted rotation around a single bond. In particular, biaryl atropisomers represent an important class of compounds, as they are widely present in natural products, ligands and pharmaceutical molecules. However, the preparation of structurally diverse biaryl atropisomers under mild conditions is a significant challenge. Here, we describe a Cu-bis(oxazolinyl)pyridine-catalyzed asymmetric ring-opening amination reaction of cyclic diaryliodoniums. Increasing the torsional strain of these cyclic compounds significantly improved the reactivity of cyclic diaryliodoniums. Computational investigation indicated that the two conformers of the cyclic diaryliodoniums had a low rotational barrier, and generally the reaction achieved high yields and high enantioselectivity (up to >99% ee). Furthermore, this ring-opening amination reaction also featured high atom economy in comparison with traditional reactions involving diaryliodonium. Finally, we propose a catalytic cycle and a mechanistic model that accounts for the observed enantioselectivity.

Site-selective synthesis of functionalized dibenzo[f,h]quinolines and their derivatives involving cyclic diaryliodonium salts via a decarboxylative annulation strategy.

Here we report a site-selective synthesis of functionalized dibenzo[f,h]quinolines and their derivatives, which could be used as OLED materials. The key step is the double cross coupling reaction between the 2-chloropyridinyl acids and the cyclic diaryliodonium salts, where the carboxylic acid was unprecedentedly employed as both a traceless directing group and a functional handle in a one-pot atom- and step-economical process.

Construction of Functionalized Annulated Sulfone via SO2/I Exchange of Cyclic Diaryliodonium Salts.

A straightforward protocol for diarylannulated sulfone construction is efficiently established via SO2/I exchange of iodonium(III) salts. Readily available inorganic Na2S2O5 was served as a safe and convenient SO2 surrogate. Diverse functionalized diarylannulated sulfones were smoothly achieved in good to excellent yields with great functional group compatibility. Organic light emitting diodes (OLEDs) material molecules were subsequently established via this method in gram scale. The unsymmetrical conjugated systems with donor-acceptor groups and π-conjugation bridges motifs, which substantially communicate electron mobility in semiconductor material molecules, were successfully afforded under the facile conditions of the exchange strategy.

Synthesis of Functionalized Biaryls and Poly(hetero)aryl Containing Medium-Sized Lactones with Cyclic Diaryliodonium Salts.

A novel one-pot procedure is described for the transition-metal catalyzed sequential difunctionalization of diaryliodonium reagents. Reaction of commercially available anthranilic acid derivatives with readily available cyclic diaryliodonium salts followed by a Sonogashira coupling afforded various alkyne substituted biaryls in good to excellent yields. The functionalized biaryls were then utilized for the rapid and efficient one-pot synthesis of novel poly(hetero)aryl containing 10-membered lactones which are potential G-quadruplex binders and telomerase inhibitors.