A Thorium(IV) metallacyclopropyne complex.

Actinide metallacyclic chemistry  has been of interest due to its involvement  in various chemical processes. However, fundamental understanding on the key species, actinide metallacyclic complexes, is limited to metallacyclopropenes whereas little is known about the actinide metallacyclopropynes presumably due to their unusual high reactivity. Herein, we report the preparation of a thorium metallacyclopropyne complex (η-C ≡ C)ThCl in the gas phase by using electrospray ionization mass spectrometry, and it is generated via a single-ligand strategy through sequential losses of CO and HCl from the monopropynoate precursor (HC ≡ CCO)ThCl upon collision-induced dissociation.

Formation and Structure of Gas-Phase Lanthanide(III) Cyanobenzyne Complex (η-4-CNCH)LnCl, Obtained via Both the Single- and Dual-Ligand Strategies.

The lanthanide(III) cyanobenzyne complexes (η-4-CNCH)LnCl (Ln = La-Lu except Eu; Pm was not examined) were generated in the gas phase using an electrospray ionization mass spectrometry coupled with collision-induced dissociation (CID) technique. For all lanthanides except Sm, Eu, and Yb, (4-CNCH)LnCl can be generated either via a single-ligand strategy through consecutive CO and HCl losses of (4-CNCHCO)LnCl or via a dual-ligand strategy through successive CO/CHCN or 4-CNCHCOH and CO losses of (4-CNCHCO)LnCl. For Sm and Yb, although only reduction products LnCl were formed upon CID of (4-CNCHCO)LnCl, (4-CNCH)LnCl were obtained via the dual-ligand strategy without the appearances of other products.