Pd(II)-Mediated BT(S)-Alkene Rearrangement – Paper Now In Press

As part of the Organometallic Solutions to Challenges in Cross-Coupling special issue in Organometallics, our lab reports an usual rearrangement process triggered by addition of Pd(TFA)2 to alkenes containing a benzothiazole thioether (BT(S)) directing group. The transformations furnishes a structurally family of previously unknown tetrahydrothiophene-functionalized N,S-heterocyclic carbene palladium(II) complexes that are catalytically active in various C–C coupling reactions. Congrats to grad student Andrew, former high school intern Matt, as well as our treasured X-ray crystallography collaborators Milan and Arnie from UCSD.

For a link to the accepted manuscript, click here: https://pubs.acs.org/doi/10.1021/acs.organomet.1c00041

The work first appeared on ChemRxiv back in January. Check out the pre-print here: https://chemrxiv.org/articles/preprint/Ligand_Rearrangement_Leads_to_Tetrahydrothiophene-Functionalized_N_S-Heterocyclic_Carbene_Palladium_II_Complexes/13633301

Van successfully defends her thesis

Congrats to Van Tran, Ph.D., who successfully defended her thesis earlier today, become the fifth Ph.D. graduate from the group (and second to defend online). Van has made pioneering contributions in diverse areas, including developing a new approach to C(sp3)–C and C(sp3)–heteroatom bond cleavage under palladium catalysis, demonstrating the power of nickel for catalyzing conjunctive cross-coupling reactions with alkenes, and inventing a series of a new low-valent nickel pre-catalysts. Congrats on all of your success, Van! Best of luck in your next adventure as as a process chemist at Gilead.

CAAC Ligands Enable Unique Selectivity in Copper–Boryl Pi-Bond Addition Processes – Pre-Print Now Online

In collaboration with the labs of Profs. Guy Bertrand (UC San Diego) and Doug Grotjahn (San Diego State), we have discovered that that cyclic (amino)(alkyl)carbene (CAAC) ligands, which have been extensively developed in the Bertrand lab over the past several years, when coordinated with copper yield catalysts with unique selectivity in classical copper–boryl alkyne addition reactions. Specifically, we developed highly general Markovnikov-selective protoboration and -silylation protocol of terminal alkynes that is agnostic to the electronic properties of both the alkyne substrate and the boryl/silyl nucleophile. This represents first report from a powerful new collaboration between three groups across three institutions in San Diego. Congrats to the entire authorship team: Yang, Aaron, and Keary (Scripps); Sima (SDSU/UCSD); Doug (SDSU); and Glen, Rudy, and Guy (UCSD).

For a link to the pre-print, click here: https://chemrxiv.org/articles/preprint/Cyclic_Alkyl_Amino_Carbene_Ligands_Enable_Cu-Catalyzed_Markovnikov_Protoboration_and_Protosilylation_of_Terminal_Alkynes_A_Versatile_Portal_to_Functionalized_Alkenes/14368607