Student Inorganic Chemistry Seminar with Chonghe Zhang (MIT- Cummins Group & Gilliard Group)

Title: Access to Low-Valent Boron via Mild Fragmentation Abstract: Low-valent boron compounds remain far less developed than their carbon analogues, largely due to their high reactivity, limited stability, and the difficulty of controlling their generation. Among these species, borylenes have emerged as highly promising intermediates for small-molecule activation and bond-forming reactions. However, state-of-the-art approaches to borylenes typically rely on strong reducing reagents or harsh conditions, which restrict functional-group compatibility and practical applications. We explored alternative and milder strategies for accessing borylenes and boryl anions without the use of aggressive reagents. Two precursors, boranorbornadiene and diazoborane, will be presented, with particular emphasis on the diazoborane platform. Detailed investigations of electronic structure and reactivity reveal intriguing parallels to diazoalkanes, while also highlighting key distinctions arising from boron’s unique valence and orbital characteristics. This strategy provides new opportunities for downstream transformations, particularly small-molecule activation and selective C–H borylation reactions that are more compatible with common organic functional groups. More broadly, this work establishes a conceptual framework for the design of practical precursors to low-valent main-group intermediates. Pizza will be served outside of 4-370 at 3:45PM.