Electrochemical Preparation of Sm(II) Reagent Facilitated by Weakly Coordinating Anions.

Samarium diiodide (SmI ) is widely used as a strong one-electron reducing agent and is often employed to form C-C bonds in complex systems. Despite their utility, SmI and related salts suffer from several drawbacks that render the use of Sm reducing agents in large-scale synthesis impractical. Here, we report factors influencing the electrochemical reduction of Sm(III) to Sm(II), towards the goal of electrocatalytic Sm(III) reduction.

Iterative Supervised Principal Component Analysis Driven Ligand Design for Regioselective Ti-Catalyzed Pyrrole Synthesis.

The rational design of catalysts remains a challenging endeavor within the broader chemical community owing to the myriad variables that can affect key bond-forming events. Designing selective catalysts for any reaction requires an efficient strategy for discovering predictive structure-activity relationships. Herein, we describe the use of iterative supervised principal component analysis (ISPCA) in catalyst design.

Synthesis of pentasubstituted 2-aryl pyrroles from boryl and stannyl alkynes one-pot sequential Ti-catalyzed [2 + 2 + 1] pyrrole synthesis/cross coupling reactions.

Multisubstituted pyrroles are commonly found in many bioactive small molecule scaffolds, yet the synthesis of highly-substituted pyrrole cores remains challenging. Herein, we report an efficient catalytic synthesis of 2-heteroatom-substituted (9-BBN or SnR) pyrroles Ti-catalyzed [2 + 2 + 1] heterocoupling of heteroatom-substituted alkynes. In particular, the 9-BBN-alkyne coupling reactions were found to be very sensitive to Lewis basic ligands in the reaction: exchange of pyridine ligands from Ti to B inhibited catalysis, as evidenced by B NMR studies.