New and versatile routes to zirconium imido dichloride compounds

Reactions of zirconium dialkyl- or bis(amido) - dichloride complexes "[Zr(CH(2)SiMe(3))(2)Cl(2)(Et(2)O)(2)]" or [Zr(NMe(2))(2)Cl(2)(THF)(2)] with primary alkyl and aryl amines are described. Reaction of "[Zr(CH(2)SiMe(3))(2)Cl(2)(Et(2)O)(2)]" with RNH(2) in THF afforded dimeric [Zr(2)(mu- NR)(2)Cl(4)(THF)(4)] (R = 2,6-C(6)H(3) (i)Pr(2) ( 1), 2,6-C(6)H(3)Me(2) (2) or Ph(3)), [Zr(2)(mu-NR)(2)Cl(4)(THF)(3)] (R = (t)Bu ( 5), (i)Pr (6), CH(2)Ph (7)), or the "ate" complex [Zr(2)(mu-NC(6)F(5))(2)Cl(6)(THF)(2) {Li(THF)(3)}(2)] (4, the LiCl coming from the in situ prepared "[Zr(CH(2)SiMe(3))(2)Cl(2)(Et(2)O)(2)]"). With [Zr(NMe(2))(2)Cl(2)(THF)(2)] the compounds [Zr(2)(mu-NR)(2)Cl(4)(L)(x) (L')(y)] (R = 2,6-C(6)H(3) (i)Pr(2) (8), 2,6-C(6)H(3)Me(2) (9), Ph (10) or C(6)F(5) ( 11); (L)(x) (L')(y) = (NHMe(2))(3)(THF), (NHMe(2))(2)(THF)(2) or undefined), [Zr(2)(mu- N(t)Bu)(2)Cl(4)(NHMe(2))(3)] ( 12) and insoluble [Zr(NR) Cl(2)(NHMe(2))](x) (R = (i)Pr (13) or CH(2)Ph (14)) were obtained. Attempts to form monomeric terminal imido compounds by reaction of 2 or 5 with an excess of pyridine led, respectively, to the corresponding dimeric adducts [Zr(2)(mu-2,6-C(6)H(3)Me(2))(2)Cl(4)(py)(4)] ( 15) and [Zr(2)(mu-N(t)Bu)(2)Cl(4)(py)(3)] (16). The X-ray structures of 1, 2, 4, 8, 12 and 15 have been determined.