Ligand- and Base-Free Access to Diverse Biaryls by the Reductive Coupling of Diaryliodonium Salts

BODIPY(aryl)iodonium salts in the efficient synthesis of diversely functionalized BODIPYs and selective detection of serum albumin

BODIPY(aryl)iodonium salts were readily accessible from the high-yielding reaction of BODIPY with iodoarenes or hydroxyl(tosyloxy)iodoarenes in the presence of m-CPBA. The prepared BODIPY(aryl)iodonium salts bearing substituents of varied electronic nature were utilized for the direct syntheses of thiocyanate, azide, amine and acrylate functionalized BODIPYs and β,β'-bis-BODIPYs. The regioselective syntheses of α-piperidinyl and β-piperidinyl substituted BODIPYs were achieved through the reaction of BODIPY(aryl)iodonium salts with piperidine in the absence and presence of copper(I). Expeditious and high yielding (79-82%) synthesis of β,β'-bis-BODIPYs was also developed through the palladium-catalyzed reductive coupling of the easily accessible BODIPY(aryl)iodonium salts. Some of the indole-appended BODIPYs and bis-BODIPYs displayed strong absorption in the visible region (∼610 nm). The BODIPY(aryl)iodonium salts also showed significant binding with serum albumin and were observed to be selective serum protein sensors with estimated limits of detection as low as 7 μg mL-1 in some cases.

Temporary (P[double bond, length as m-dash]O) directing group enabled carbazole ortho arylation via palladium catalysis

A palladium-catalyzed, temporary P(O) directing group assisted C-H bond arylation of carbazoles was achieved. The release of the directing group occurs spontaneously in the reaction and the mechanistic studies indicate that acid is essential for N-P bond cleavage.

Characterization of heterogeneous aryl–Pd(ii)–oxo clusters as active species for C–H arylation

The surface oxidation of Pd nanoparticles with [Ph₂I]BF₄ resulted in the generation of Pd(ii)–aryl–oxo clusters, which led to C–H arylation in high yields and regioselectivity.

An efficient synthesis of triazolium ion based NHC precursors using diaryliodonium salts and their photophysical properties

Copper-catalysed N-arylation of fused triazoles using diaryliodonium salts as an aryl source is described. This scalable protocol displayed good compatibility towards diverse sensitive functional groups like ester, alkyl and nitro groups and halogens (F, Cl, Br). The synthetic usefulness of the prepared triazolium salts was proved by preparing α-hydroxyketone through benzoin condensation. Photophysical studies of these compounds showed promising Stokes-shifted fluorescence emission in aqueous medium, so this molecular framework could be a proficient probe for biological applications.

Metal-catalyzed direct heteroarylation of C-H (meso) bonds in porphyrins: facile synthesis and photophysical properties of novel meso-heteroaromatic appended porphyrins

A simple and rapid microwave-assisted synthesis of heteroaromatic appended porphyrins using the Pd/Cu-catalyzed C-C coupling of meso-bromoporphyrins with various five- and six-membered heteroaromatic azoles has been successfully developed. The prepared heteroaromatic porphyrins 7a-lNi were found to exhibit slightly red-shifted (∼5-10 nm) Soret and Q bands. The developed reaction conditions are useful for the preparation of diversely substituted heteroaromatic porphyrins (A₃B- and A₂B₂-types).

Iridium- and Rhodium-Catalyzed Directed C-H Heteroarylation of Benzaldehydes with Benziodoxolone Hypervalent Iodine Reagents

The C-H heteroarylation of benzaldehydes with indoles and pyrroles was realized using the benziodoxolone hypervalent iodine reagents indole- and pyrroleBX. Functionalization of the aldehyde C-H bond using either an o-hydroxy or amino directing group and catalyzed by an iridium or a rhodium complex allowed the synthesis of salicyloylindoles and (2-sulfonamino)benzoylindoles, respectively, with good to excellent yields (74-98%). This new transformation could be carried out under mild conditions (rt to 40 °C) and tolerated a broad range of functionalities, such as ethers, halogens, carbonyls, or nitro groups.

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.

Tuning the ambipolar charge transport properties of tricyanovinyl-substituted carbazole-based materials

The ambipolar charge transport properties of a series of push–pull carbazole-based semiconductors are here evaluated. The ambipolar characteristics depend on the supramolecular organization. Experimental results were confirmed and justified through the X-ray analysis of single crystals and by theoretical calculations.