Congrats to Dr. Nana Kim, who completes her postdoc this week. During her time in the Engle lab, Nana spearheaded new directions in nickel pre-catalyst development, including the identification of Ni(COD)(DMFU) as a potent precatalyst for alkene diarylation and development of a versatile bench-stable Ni(0) precatalyst for a variety of important catalytic reactions. Nana will soon start her career as a process chemist at Bristol Myers Squibb in New Brunswick, NJ. We wish you the best of luck in your new adventure, Nana!
Congrats to the Engle lab’s newest doctor, Tanner C. Jankins, Ph.D.! In Tanner’s Ph.D. research, he spearheaded a new research directing focused on W(0)/W(II) redox catalysis, where non-classical seven coordinate geometries at W(II) can be exploited to enable facile alkene isomerization–functionalization processes. Outside of the lab, Tanner served as Engle group chef, the Scripps resident extreme sports instructor, and organometallics grad course TA. Congratulation on all of your success Tanner! Tanner will soon start his postdoc in the lab of Prof. Bill Morandi at ETH Zürich.
In collaboration with chemistry from Cornell University, Bristol Myers Squibb, and UC San Diego, today we report the culmination of a multi-year effort to identify new bench-stable Ni(0) precatalysts with coordination properties that complement Ni(COD)(DQ) (COD = 1,5-cyclcooctadiene, DQ = duroquinone) in terms of reactivity and stability. After surveying upwards of 100 ligands, we identified 10 18-electron complexes of the type Ni(COD)(L), where L = quinone, cyclopentadienone, thiphene-S-oxide, of fulvene) that are remarkable air-stable in solid and solution state. We characterized this family of complexes using NMR, X-ray crystallography, IR, NBO analysis, CV, and TGA, and showed how their kinetic behavior varies when used as pre-catalysts in a variety of Ni-catalyzed reactions from the literature. Congrats to the whole team, especially project leads Van and Nana!
For a link to the ChemRxiv pre-print, click here: https://chemrxiv.org/engage/chemrxiv/article-details/62034cfce0f52929aeac5fd0
The latest results from our collaboration on (CAAC)Cu catalysis (CAAC = cyclic(alkyl)(amino)carbene) with the Grotjahn lab (SDSU) and Betrand lab (UCSD) are described in a pre-print appearing today in ChemRxiv. Building on our previous discovery that strong σ-donating CAAC ligands can effectively quench the Lewis acidity of boryl ligand on the Cu center and promote regioselective boryl transfer to the internal (α) position (Angew. Chem. Int. Ed. 2021, 60, 19871) in protoboration, in the current study we extend this concept to a number of C(sp3) electrophiles. This protocol allows for expedient and selective assembly of alkenylboron products that are versatile building blocks in synthesis. Hats off to the tri-institutional team: Yang, Nana, Sima, Mingyu, Aaron, Doug, Guy, Rudy, and Keary!
For a link to the ChemRxiv pre-print, click here: https://chemrxiv.org/engage/chemrxiv/article-details/61f8b9da360c842812b1d6c2