Probing the Visible Light-Driven Geometrical Isomerization of 4-Arylbut-3-ene-2-amines.

A series of thirteen 4-arylbut-3-ene-2-amines were prepared and subjected to photosensitization experiments to interrogate their photostationary state (PS) composition of geometrical olefin isomers (E and Z). The amine PS compositions were found to depend on arene structure and temperature, while being largely independent of nitrogen substitution, solvent, or presence of triplet-quenching oxygen. Photonic efficiency of isomerization (ζ) was found to depend on amine structure, solvent choice, and presence of quencher.

Exploiting Visible Light Triggered Formation of -Cyclohexene for the Contra-thermodynamic Protection of Alcohols.

We report herein a method for the contra-thermodynamic protection and thermodynamic deprotection of alcohols in which all reagents are returned to their original state. This is accomplished by the use of visible light photochemical energy to drive the formation of a highly strained -()-cyclohexene. At STP the product ethers contain more potential energy than the starting materials and, thus, can be catalytically returned to the starting materials, effectively realizing a protection-deprotection scheme paid for with an energy currency.

A Selective Single Step Amidation of Polyfluoroarenes.

This chemistry establishes a method for the synthesis of per- and poly-fluoroaryl acid amides, utilizing nucleophilic aromatic substitution. Traditionally, such amides are constructed in a two-step process, namely, ammonolysis and then -acylation. Herein, good yields of polyfluoroaryl acid amides were achieved in a single step under mild reaction conditions.