Synthesis and Lanthanide Coordination Chemistry of Phosphine Oxide Decorated Dibenzothiophene and Dibenzothiophene Sulfone Platforms

Abstract

Syntheses for new ligands based upon dibenzothiophene and dibenzothiophene sulfone platforms, decorated with phosphine oxide and methylphosphine oxide donor groups, are described. Coordination chem. of 4,​6-​bis(diphenylphosphinoylmethyl)​dibenzothiophene (8)​, 4,​6-​bis(diphenylphosphinoylmethyl)​dibenzothiophene-​5,​5-​dioxide (9) and 4,​6-​bis(diphenylphosphinoyl)​dibenzothiophene-​5,​5-​dioxide (10) with lanthanide nitrates, Ln(NO3)​3·(H2O)​n is outlined, and crystal structure detns. reveal a range of chelation interactions on Ln(III) ions. The HNO3 dependence of the solvent extn. performance of 9 and 10 in 1,​2-​dichloroethane for Eu(III) and Am(III) is described and compared against the extn. behavior of related dibenzofuran ligands (2, 3; R = Ph) and n-​octyl(phenyl)​-​N,​N-​diisobutylcarbamoylmethyl phosphine oxide (4) measured under identical conditions.