Photochemical Formation of Trifluoroacetic Acid: Mechanistic Insights into a Fluoxetine-Related Aryl-CF Compound.

Trifluoroacetic acid (TFA) is a ubiquitous environmental contaminant; however, its sources are poorly constrained. One understudied source is from the photochemical reactions of aromatic compounds containing -CF moieties (aryl-CF) including many pharmaceuticals and agrochemicals. Here, we studied the aqueous photochemistry of 4-(trifluoromethyl)phenol (4-TFMP), a known transformation product of the pharmaceutical fluoxetine.

Combining Enantioselective Rh-Catalyzed Conjugate Addition and Ir-Catalyzed Allylic Alkylation in Stereodivergent, Multicomponent Coupling Reactions to Form Three Stereocenters.

Stereodivergent dual catalysis has emerged as a powerful tool to selectively prepare all four stereoisomers in molecules containing two chiral centers from common starting materials. Most processes involve the use of two substrates, and it remains challenging to use dual catalyst approaches to generate molecules having three newly formed stereocenters with high diastereo- and enantioselectivity. Here we report a multicomponent, stereodivergent method for the synthesis of targets containing three contiguous stereocenters by the combination of enantioselective Rh-catalyzed conjugate addition and Ir-catalyzed allylic alkylation methodologies.

Site-Selective Hydrogenation of Electron-Poor Alkenes and Dienes Enabled by a Rhodium-Catalyzed Hydride Addition/Protonolysis Mechanism.

The transition metal catalyzed hydrogenation of alkenes is a well-developed technology used on lab scale as well as on large scales in the chemical industry. Site- and chemoselective mono-hydrogenations of polarized conjugated dienes remain challenging. Instead, stoichiometric main-group hydrides are used rather than H .

Fast Carbon Isotope Exchange of Carboxylic Acids Enabled by Organic Photoredox Catalysis.

Carbazole/cyanobenzene photocatalysts promote the direct isotopic carboxylate exchange of C(sp) acids with labeled CO. Substrates that are not compatible with transition-metal-catalyzed degradation-reconstruction approaches or prone to thermally induced reversible decarboxylation undergo isotopic incorporation at room temperature in short reaction times. The radiolabeling of drug molecules and precursors with [C]CO is demonstrated.