The formation of alkyl-palladium complexes via the nucleopalladation of alkenes is the entry point for a wide range of diverse reactions. One possibility is that the intermediate alkyl-Pd complexes can undergo a "chain-walking" event, to allow for remote functionalization through various termination processes. However, there are few methods to selectively interrupt the chainwalking process at a prescribed location. Herein we demonstrate that a variety of homoallylic protected amines undergo an interrupted enantioselective relay Heck reaction to give enantioenriched allylic amine products. The selectivity of this process can be diverted to exclusively yield the ene-amide products by virtue of changing the nature of the amine protecting group. To rationalize this observation, we combine experiment and computation to investigate the mechanism of the chain-walking process and termination events. Isotopic labeling experiments and the computed reaction pathways suggest that the system is likely under thermodynamic control, with the selectivity being driven by the relative stability of intermediates encountered during chain walking. These results illustrate that the chain-walking of alkyl-palladium complexes can be controlled through the alteration of thermodynamic processes and provides a roadmap for exploiting these processes in future reaction development.

For many decades, bulk Bi2S3, a key low-bandgap metal chalcogenide semiconductor, has lagged behind in terms of potential applications due to its poor electrical properties. As such, controlling size extrinsic atom interactions in this material might emerge as a viable route to enhance its poor electrical properties. Here, we report the hydrothermal synthesis, structural characterization, and optoelectronic properties of Bi2S3‑x Se x solid solutions. Optical characterizations show a decrease in the bandgap of Bi2S3 nanowires as a function of Se concentrations. Furthermore, ensemble electrical transport measurements suggest a pronounced increase in the electrical properties of Bi2S3 nanowires upon Se incorporation. This study points to the importance of carefully controlling the stoichiometry and sizes in Bi2S3 as a way to favorably tune its optoelectronic properties.

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