A mild, modular, and practical catalytic system for the synthesis of the highly privileged phenethylamine pharmacophore is reported. Using a unique combination of organic catalysts to promote the transfer of electrons and hydrogen atoms, this system performs direct hydroarylation of vinyl amine derivatives with a wide range of aryl halides (including aryl chlorides). This general and highly chemoselective protocol delivers a broad range of arylethylamine products with complete regiocontrol. The utility of this process is highlighted by its scalability and the modular synthesis of an array of bioactive small molecules.

We report the photoredox alkylation of halopyridines using functionalized alkene and alkyne building blocks. Selective single-electron reduction of the halogenated pyridines provides the corresponding heteroaryl radicals, which undergo anti-Markovnikov addition to the alkene substrates. The system is shown to be mild and tolerant of a variety of alkene and alkyne subtypes. A combination of computational and experimental studies support a mechanism involving proton-coupled electron transfer followed by medium-dependent alkene addition and rapid hydrogen atom transfer mediated by a polarity-reversal catalyst.

The intermolecular alkylation of pyridine units with simple alkenes has been achieved via a photoredox radical mechanism. This process occurs with complete regiocontrol, where single-electron reduction of halogenated pyridines regiospecifically yields the corresponding radicals in a programmed fashion, and radical addition to alkene substrates occurs with exclusive anti-Markovnikov selectivity. This system is mild, tolerant of many functional groups, and effective for the preparation of a wide range of complex alkylpyridines.

Metrics & MoreArticle Recommendations * sı Supporting Information ABSTRACT: ((R(CH 2 ) n NH 3 + cations (R = aryl, substituted cyclohexyl; n = 1, 2) can form hybrid lead iodides that include both 2D layered perovskites of formula [R(CH 2 ) n NH 3 ] 2 PbI 4 and 1D structures consisting of 1D wires of face-sharing PbI 6 octahedra and having the formula [R(CH 2 ) n NH 3 ]PbI 3 (face-sharing lead iodide chains, FSLICs). Using a series of such cations, we find that 1D FSLIC formation is favored when hydrogen bonding is possible between the ammonium moiety of one cation and a hydrogen-bond acceptor substituent of the same or another cation. A total of 16 new hybrid organic lead iodide crystal structures, 11 of which are FSLICs, are reported. The FSLIC structures can be further categorized according to the arrangement of neighboring wires. The optical properties of these materials are largely insensitive to the identity of the organic cations and to the resulting structural details. However, there is a correlation between the exciton energy and the pattern in which the wires are arranged relative to one another. Density functional theory calculations indicate that the dispersion at the top of the valence band varies depending on the relative wire arrangement.