Copper-Catalyzed Regio- and Stereoselective O-Arylation of Enolates

Copper-Catalyzed Chemoselective O-Arylation of Oxindoles: Access to Cyclic Aryl Carboxyimidates

We have developed a highly efficient base- and additive-free chemoselective CuO-catalyzed strategy for the O-arylation of 2-oxindoles to synthesize 2-phenoxy-3H-indole and 2-phenoxy-1H-indole derivatives in the presence of diaryl iodonium salts. This method offers a variety of O-arylated oxindoles in good to excellent yields under relatively milder reaction conditions. Furthermore, this methodology was extended for the O-arylation of 2-pyridinone and isoindoline-1-one derivatives as well.

Metal-Free Regioselective N2-Arylation of 1H-Tetrazoles with Diaryliodonium Salts

We describe a simple, metal-free regioselective N²-arylation strategy for 5-substituted-1H-tetrazoles with diaryliodonium salts to access 2-aryl-5-substituted-tetrazoles. Diaryliodonium salts with a wide range of both electron-rich and previously challenged electron-deficient aryl groups are applicable in this method. Diversely functionalized tetrazoles are tolerable also. We have devised a one-pot system to synthesize 2,5-diaryl-tetrazoles directly from nitriles. The synthetic utility of this method is furthered extended to late-stage arylation of two biologically active molecules.

One-pot synthesis of 3-substituted-3-hydroxyindolin-2-ones: three component coupling of N-protected isatin, aryne precursor and 1,3-cyclodione under metal-free conditions

A transition-metal free synthetic strategy for the direct synthesis of 3-substituted-3-hydroxy-indolin-2-ones via three component coupling of N-protected isatin, aryne precursor, and 1,3-cyclodione.

Transition-metal-free α-arylation of nitroketones with diaryliodonium salts for the synthesis of tertiary α-aryl, α-nitro ketones

Transition-metal-free α-arylation of α-nitroketones with diaryliodonium salts has been developed for the first time and applied in the synthesis of tiletamine.

SF5-Pyridylaryl-λ3-iodonium salts and their utility as electrophilic reagents to access SF5-pyridine derivatives in the late-stage of synthesis

Electrophilic pentafluorosulfanyl (SF₅) heteroarylation of target molecules using novel reagents is described. Unsymmetrical diaryliodonium reagents 1 having 2-SF₅-pyridine have been synthesized in good yields. They are efficient electrophilic reagents for carbon and heterocentered nucleophiles, producing the corresponding SF₅-pyridine derivatives in good to excellent yields.

Metal-free regioselective formation of C-N and C-O bonds with the utilization of diaryliodonium salts in water: facile synthesis of N-arylquinolones and aryloxyquinolines

Regioselective construction of crucial C-N and C-O bonds leading to N-arylquinolones and aryloxyquinolines has been accomplished by employing easily accessible diaryliodonium salts and quinolones in water under metal- and ligand-free conditions. This operationally simple strategy is significant due to mild reaction conditions, high product yields, recyclability of released iodoarenes and scalability to the gram level. The practical utility of the developed protocol was proved by the arylation of medicinally important heterocycles like acridin-9(10H)-one, 3-methylquinoxalin-2(1H)-one and 1H-benzo[d]imidazol-2(3H)-one.

Palladium-catalyzed aerobic regio- and stereo-selective olefination reactions of phenols and acrylatesviadirect dehydrogenative C(sp2)–O cross-coupling

An efficient olefination protocol for the oxidative dehydrogenation of phenols and acrylates has been achieved using a palladium catalyst and O₂as the sole oxidant.

Electrophilic Triflyl-arylation and Triflyl-pyridylation by Unsymmetrical Aryl/Pyridyl-λ3-iodonium Salts: Synthesis of Aryl and Pyridyl Triflones

Unsymmetrical diaryl-λ³-iodonium salts containing aryl triflone (Ar-SO₂CF₃) were designed and synthesized. X-ray crystal structure analysis of the salt indicated a T-shaped geometry at the iodine atom. The salts were found to be powerful electrophilic reagents for triflyl-arylation of C-, N-, and O-centered nucleophiles under mild conditions. Electrophilic transfer of pyridine triflone (Py-SO₂CF₃) to nucleophiles was also realized by the use of corresponding triflylpyridyl-aryl-λ³-iodonium salts. Selection of auxiliaries (dummy ligands) of unsymmetrical diaryl-λ³-iodonium salts is crucial for this transformation.

Stereoselective Synthesis of (E)-β-Aryloxyl and Alkyloxyl Acrylates Through DABCO-Catalysed Michael Additions of Phenols and Alcohols to Ethyl 2,3-Butadienoate

The development of DABCO-catalysed Michael addition of phenols and alcohols to ethyl 2,3-butadienoate provides an efficient synthetic pathway to ( E)- β-aryloxyl and alkyloxyl acrylates in i-PrOH or under solvent-free conditions. The major advantages of the present method are wide substrate scope, mild reaction conditions, high stereoselectivity, and good reaction yields.

Arylation with Diaryliodonium Salts

This chapter focuses on recent developments in metal-free and metal-catalyzed arylations with diaryliodonium salts (diaryl-λ3-iodanes). Synthetic routes to diaryliodonium salts are briefly described, and chemoselectivity trends with unsymmetric iodonium salts are discussed.

Synthesis of Diaryliodonium Salts Having Pentafluorosulfanylarenes and Their Application to Electrophilic Pentafluorosulfanylarylation of C-, O-, N-, and S-Nucleophiles

Novel reagents for the electrophilic introduction of pentafluorosulfanyl (SF5) arenes into target molecules are disclosed. Unsymmetrical diaryliodonium salts 1 having SF5-arenes were synthesized by a one-pot process from iodo-SF5-benzenes 2 in good yields. The SF5-aryliodonium salts 1 were found to be efficient for the electrophilic SF5-arylation of carbon and heterocentered nucleophiles to furnish the corresponding substituted SF5-arenes in good to high yields.

Copper-catalyzed three-component reactions of phenols, acyl chlorides and Wittig reagents for the synthesis of β-aryloxyl acrylates

A new protocol towards the diversity-oriented synthesis of β-aryloxyl acrylates has been developed using simple reactants and catalyst.