LAUSR

Abstract The reactivity of the yttrium trichloride complex [Cl 3 Y{(μ 3 -NH) 3 Ti 3 (η 5 -C 5 Me 5 ) 3 (μ 3 -N)}] ( 2 ) with a variety of main-group metal cyclopentadienyl reagents [M(C 5 H 3 R 1 R 2 )] (M = Li, Na, K, Tl) or [Mg(C 5 H 5 ) 2 ] has been investigated. Treatment of 2 with one equivalent of [Na(C 5 H 5 )] or [K(C 5 H 4 SiMe 3 )] gives the monocyclopentadienyl derivatives [(η 5 -C 5 H 4 R)Cl 2 Y{(μ 3 -NH) 3 Ti 3 (η 5 -C 5 Me 5 ) 3 (μ 3 -N)}] (R = H ( 3 ), SiMe 3 ( 4 )). Analogous reaction of 2 with lithium [Li(C 5 H 3 R 1 R 2 )] or thallium [Tl(C 5 H 5 )] reagents (1 or 2 equivalents) leads to complexes [(η 5 -C 5 H 3 R 1 R 2 ) 2 Y(μ-Cl) 2 M{(μ 3 -NH) 3 Ti 3 (η 5 -C 5 Me 5 ) 3 (μ 3 -N)}] (M = Li, R 1  = R 2  = H ( 5 ), R 1  = H, R 2  = SiMe 3 ( 6 ), R 1  = R 2  = SiMe 3 ( 7 ); M = Tl, R 1  = R 2  = H ( 8 )). Complex 2 reacts with [Mg(C 5 H 5 ) 2 ] to yield the ionic compound [(μ-Cl) 3 Mg 2 {(μ 3 -NH) 3 Ti 3 (η 5 -C 5 Me 5 ) 3 (μ 3 -N)} 2 ][{Y(η 5 -C 5 H 5 ) 2 Cl} 2 (μ-Cl)] ( 9 ). In contrast to the metathesis of chloride ligands, the reaction of 2 with the lithium indenyl derivative [Li(C 9 H 7 )] at room temperature produces C 9 H 8 and the precipitation of [Li(μ-Cl) 3 Y{(μ 3 -N)(μ 3 -NH) 2 Ti 3 (η 5 -C 5 Me 5 ) 3 (μ 3 -N)}] ( 10 ). Crystallization of 10 in pyridine affords the lithium-free [Cl 2 (py) 2 Y{(μ 3 -N)(μ 3 -NH) 2 Ti 3 (η 5 -C 5 Me 5 ) 3 (μ 3 -N)}] ( 11 ) complex. The X-ray crystal structures of 6 and 11 have been determined.