Rare-earth-metal trimethylsilylmethyl ate complexes

Area of Science:

• Organometallic Chemistry
• Rare-Earth Chemistry
• Main Group Chemistry

Background:

• Rare-earth metal alkylidene complexes are valuable synthetic intermediates.
• Schumann's protocol provides a route to these compounds.
• Exploration of early rare-earth metals is less common.

Purpose of the Study:

• To synthesize and characterize novel rare-earth metal neosilyl ate complexes.
• To investigate the potential for alkylidene formation from these complexes.
• To apply synthetic strategies to yttrium, scandium, and lanthanum.

Main Methods:

• Reaction of rare-earth metal chlorides (YCl3, ScCl3, LaCl3) with lithium neosilyl (LiCH2SiMe3).
• Characterization using multinuclear NMR spectroscopy (1H, 13C, 7Li, 29Si, 89Y) and DRIFT spectroscopy.
• Thermolysis of yttrium complex and reactivity studies with benzophenone.

Main Results:

• Isolation and characterization of tetrametallic Li3Y(CH2SiMe3)6 with an unprecedented structure.
• Synthesis of ate complexes [Li(thf)4][LiSc2(CH2SiMe3)8] and [Li(thf)4][La(CH2SiMe3)4(thf)].
• Evidence for alkylidene formation from thermolysis of the yttrium complex.

Conclusions:

• Novel rare-earth metal neosilyl ate complexes were successfully synthesized.
• The study demonstrates the formation of unique structural motifs in the solid state.
• Alkylidene formation upon decomposition is supported by experimental evidence.