Date of Award




Document Type

Master's Thesis

Degree Name

Master of Science (MS)


Department of Chemistry

Content Description

1 online resource (viii, 52 pages) : illustrations (some color)

Dissertation/Thesis Chair

Marina A Petrukhina

Committee Members

Evgeny Dikarev


DBCOT, dibenzocyclooctatetraene, dibenzo[ae]cyclooctatetraene, Lanthanide, Rare Earth, Rare earth metals, Rare earth metal catalysts

Subject Categories

Chemistry | Inorganic Chemistry


A set of novel complexes of rare earth elements, M(III) = Y, La, Gd, Tb, and Dy, with the doubly-reduced dibenzo[a,e]cyclooctatetraene (DBCOT) anion has been synthesized and crystallographically characterized for the first time. Preparation of new complexes has been accomplished through the ligand-metathesis reaction of M(III) triiodides with K2(DBCOT) in THF at ambient conditions. Subsequent crystallization via slow solvent evaporation afforded single crystals of good quality. X-ray diffraction technique confirmed that all complexes are isomorphous and conform to the [M(DBCOT)(THF)4][M(DBCOT)2] composition. In their crystal structures, the monoanionic double-decker sandwiches, [M(DBCOT)2], weakly interact with the cationic counterparts, [M(DBCOT)(THF)4]+. In both parts, the DBCOT2 anions exhibit η8-coordination to metal centers with the MCDBCOT bond length distances following the trends in ionic radii for the rare earth metals. In addition to single-crystal X-ray diffraction, all products have been characterized using UV-vis and IR spectroscopic methods. The complexes of diamagnetic Y(III) and La(III) have also been characterized by 1H NMR spectroscopy. This new family represents the first structurally characterized homoleptic complexes of lanthanides with the doubly-reduced DBCOT2 anions, opening up broad investigation of their properties and applications.