Synthesis and Characterization of (Mono)pentamethylcyclopentadienyl Lutetium Complexes: Formation of Bipyridyl-Stabilized Alkyls, Anilides, and Terminal Acetylides

The alkyl complex [Lu(CH2SiMe3)3(THF)2] reacts with pentamethylcyclopentadiene (Cp*H),
giving [Cp*Lu(CH2SiMe3)2(THF)] (1). Complex 1 reacts with 1,2-dimethoxyethane (DME),
affording [Cp*Lu(CH2SiMe3)2(DME)] (2). Complex 1 also reacts with 2,2‘-bipyridine (bipy)
to give [Cp*Lu(CH2SiMe3)2(bipy)] (3). The dialkyl complex 3 reacts with 1.0 equiv of 2,6-diisopropylaniline to give the mixed alkyl-anilide [Cp*Lu(NHAr)(CH2SiMe3)(bipy)] (4)
(Ar = 2,6-Pri2C6H3) and the bis(anilide) [Cp*Lu(NHAr)2(bipy)] (5) in a 1.0:0.09 ratio. Complex
5 can be independently synthesized in high yield by treatment of 3 with 2.0 equiv of 2,6-diisopropylaniline or 4 with 1.0 equiv of 2,6-diisopropylaniline. Complex 3 also reacts with
2.0 equiv of phenylacetylene to afford dimeric [{Cp*Lu(CCPh)(bipy)}2(μ-η2:η2-PhC4Ph)]·2(C6H6) (6). Complex 6 reacts with THF and pyridine (py), giving terminal (bis)acetylide
complexes [Cp*Lu(CCPh)2(bipy)(THF)] (7) and [Cp*Lu(CCPh)2(bipy)(py)] (8), respectively.
The solid-state structures of 1, 2, 4, 5, 6, and 8 are reported.