Treatment of the methylene/silyl complex Cp*2Ru2(μ-CH2)(SiMe 3)(μ-Cl) with ethyne in toluene gives several products resulting from carbon-carbon bond coupling reactions; these include the first unsubstituted π-metallabenzene complex, Cp*2Ru2(n2:n5-C 5H5)(SiMe3), 1, the arene complex [Cp*Ru(n6-C6H6)]Cl, 2, and the bridging metallacyclopentadiene complex Cp*2Ru2(n2:n4-C 4H4)Cl2,3. Treatment of [Cp*RuCl2]2 with propadiene also leads to a carbon-carbon bond coupling reaction, and the product is the tetramethyleneethane (i.e., 2,2'-biallyl) complex Cp*2Ru2(n3:n3-C 6H6)Cl4, 4. A single-crystal X-ray diffraction study of 1 shows that the metallabenzene ring is π-bonded to a second metal center and that the trimethylsilyl group is a terminal ligand on the ruthenium center that lies in the metallabenzene ring plane. The aromaticity of the metallabenzene ring in 1 is also discussed.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry