title: Azide addition to give a tetra-azazirconacycle complex.
abstract: Addition of the dilithium salt, ortho-(Me3SiNLi)2C6H4, to ZrCl4 affords a base-free, D2d-symmetric complex Zr(IV)[ortho-(Me3SiN)2C6H4]2 (2), with rigorously planar ortho-phenylenediamine ligands. Lewis acidic 2 readily coordinates donor ligands such as NHEt2 to give the five-coordinate complex, Zr(IV)(NHEt2)[ortho-(Me3SiN)2C6H4]2 (3), which is also accessible by the reaction of Zr(NEt2)4 with 2 equiv of ortho-(Me3SiNH)2C6H4. Aryl azides react with 2 and 3 to give an unusual tetra-azametallacycle complex, 4, via 1,2-addition of a ligand N-Si bond to the organic azide. An X-ray crystal structure of 4 reveals a planar, five-membered metallacycle comprising the zirconium atom, one nitrogen atom of the ortho-(Me3SiN)2C6H4 ligand, and all three nitrogen atoms of the aryl azide.
authors.affiliation: Department of Chemistry, 516 Rowland Hall, University of California, Irvine, California 92697, USA. aheyduk@uci.edu
authors.forename: Alan F
authors.initials: AF
authors.lastname: Heyduk
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Blackmore
authors.forename: Nicole A
authors.initials: NA
authors.lastname: Ketterer
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Ziller