Element 70 – Ytterbium

Distinct Reactivity of Trimethylytterbium toward AlMe3 and GaMe3: Synthesis of Donor‐Stabilized Dimethylytterbium

“…Addition of THF to the mono(tetramethylgallato) complex resulted in the solventseparated ion-pair [(Me 3 TACN)YbMe 2 (thf)][GaMe 4 ], which could be selectively reduced to divalent methyl complex [(Me 3 TACN)YbMe(μ-Me)] 2 . The dimethyl ytterbium complex is prone to loss of its donor, as evidenced by 1 H and 171 Yb NMR spectroscopy, and decomposes even at À 40 °C, over a few days. Finally, the presented redox approach seems unique for ytterbium since europium does not form the putative trivalent gallate precursors and the respective samarium transformations were mostly inconclusive.…”

“…After stirring for 1 h, the suspension was dried under vacuum and the residue was washed with 3 × 3 mL n-hexane, yielding 1 as a slightly off-white powder (yield: 766.2 mg, 1.700 mmol, 95 %). 1 H NMR (400 MHz, CD 3 CN, Chemistry-A European Journal 26 °C): δ 5.61 (br, 12 H, À NCH 2 ), 2.11 (br, 9 H, À NCH 3 ) ppm. Elemental analysis (%) calculated for C 9 H 21 Cl 3 N 3 Yb (389.45 g mol À 1 ): C 23.99, H 4.70, N 9.32; found.…”

“…The crude product was crystallized overnight from toluene at À 40 °C and dried in vacuo, yielding colorless crystals (40.0 mg, 0.077 mmol, 75 %). 1 (16.4 mg, 0.227 mmol) in toluene (2 mL) was added dropwise under vigorous stirring. The solution was stirred for 10 min at ambient temperature by which time a change of color to neon yellow was observed.…”

“…Crystallization at À 40 °C afforded 4 thf as orange crystals (71.7 mg, 0.124 mmol, 95 %). 1 Synthesis of [(Me 3 TACN)YbMe 2 ] 2 (5): In situ prepared 4 thf (20.0 mg, 0.035 mmol) was dissolved in 3 mL of THF and cooled to À 40 °C. Then, a filter pipette was charged with about 5 equiv.…”

“…In terms of optoelectronic/magnetic properties and chemical reactivity, each rare-earth element claims a special position within the 17-element series, so does ytterbium (element 70). [1] More recent applications linked to specific electron configurations of ytterbium include atomic clocks, ground deformation monitors, qubits for quantum communication, and NIR emitters. [2] Unique chemical reactivity emerges from the lanthanide contraction.…”