A Thiol-Free Route to Alkyl Aryl Thioethers.

Most existing methods for the synthesis of alkyl aryl thioethers require the use of mercaptans as the starting materials, which comes with practical limitations. Reactions of diaryliodonium salts with xanthate salts, easily prepared from the corresponding alcohols and CS, under the developed conditions represent an operationally simple, thiol-free method for the synthesis of these valuable compounds. The protocol features high functional group tolerance and can be applied to the late-stage C-H functionalization and for the introduction of a CDS group.

Reaction of Diaryliodonium Salts with Potassium Alkyl Xanthates as an Entry Point to Accessing Organosulfur Compounds.

Preparation of -aryl xanthates via transition-metal-catalyzed or SAr reactions is complicated by their further transformations under the utilized conditions. In contrast, S-arylation of potassium -alkyl xanthates with diaryliodonium salts proceeds under mild conditions, enabling access to substituted -aryl xanthates. The method exhibits good functional group tolerance and can be applied to the late-stage C-H functionalization of drug molecules.

Visible-Light-Driven Thioesterification of Aryl Halides with Potassium Thiocarboxylates: Transition-Metal Catalyst-Free Incorporation of Sulfur Functionalities into an Aromatic Ring.

Reactions of acceptor-substituted aryl iodides and bromides with potassium thiocarboxylates under white light irradiation allow for the preparation of -aryl thioesters including synthetically versatile -aryl thioacetates. This transition-metal and external photocatalyst-free method features extremely mild reaction conditions compared with those used in transition-metal-catalyzed protocols. Reactions proceed via the initial formation of an electron donor-acceptor (EDA) complex in the ground state, which was supported by UV-vis spectra.

Catalyst-Free Arylation of Tertiary Phosphines with Diaryliodonium Salts Enabled by Visible Light.

The visible-light-induced arylation of tertiary phosphines with aryl(mesityl)iodonium triflates to produce the quaternary phosphonium salts occurs under mild, metal, and catalyst-free conditions. Photo-excited EDA complexes between diaryliodonium salts and phosphines supposedly enable this transformation, which is difficult to achieve through the traditional ground-state reactions. Demonstrating high functional group tolerance, broad scope, and complete selectivity of the aryl group transfer, the method is particularly compatible with sterically congested phosphines, which are challenging under metal-based catalytic methods.

Electrooptical Analysis of Microbial Cell Suspensions forDetermination of Antibiotic Resistance.

The effects of ampicillin; kanamycin, chloramphenicol, and tetracycline on electrophysical characteristics of cells of sensitive (ampicillin; kanamycin, chloramphenicol) and resistant (ampicillin; kanamycin, chloramphenicol, tetracycline) Escherichia coli strains were studied. Under the action of antibiotics sensitive and resistant E. coli strains acquire different electro-optical properties.