Toggle Main Menu Toggle Search

Open Access padlockePrints

Synthesis, structural authentication, and structurally defined metalation reactions of lithium and sodium DA-zincate bases (DA = diisopropylamide) with phenylacetylene

Lookup NU author(s): Professor William Clegg, Dr Ross Harrington, Dr Luca Russo

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

In a study aimed at developing the diisopropylamido (DA) chemistry of zincates, the new lithium DA-zincate [(TMEDA) · Li(tBu)(DA) Zn(tBu)] (4) has been synthesized by an interlocking cocomplexation approach comprising mixing of its three component chemicals, LDA, tBu2Zn, and TMEDA, in a 1:1:1 ratio in hexane solution. Previously made by transamination from the corresponding TMP-zincate, the known sodium congener [(TMEDA)-Na(tBu)(DA)Zn(tBu)] (2) was also synthesized by this approach, substituting NaDA for LDA. Closely resembling each other, their molecular structures determined by X-ray crystallography can be categorized as contact ion-pair ates of TMEDA-chelated alkali metal cations linked to trigonal-planar dialkyl-Zn anions via bridging DA ligands. Reaction of 4 and 2 with phenylacetylene affords the bimetallic acetylides [((TMEDA)·Li(C≡CPh)2Zn(tBu)} 2·(TMEDA)] (5) and [((TMEDA)·Na(C≡CPh) 2Zn(tBu)}2] (6), respectively. X-ray crystallographic studies reveal 5 is a pseudodimer (tetranuclear) with two (LiCZnC) rings linked at the Zn atoms by a bridging, nonchelating TMEDA ligand; in contrast 6 adopts a distorted cubane of alternating PhC≡C and metal (2 Na, 2 Zn) corners. For comparison, the synthesis and crystal structures of the neutral zinc complexes [(TMEDA)·Zn(C≡CPh)2] (7) and [(TMEDA)·Zn(tBu)(C≡CPh)] (8), formally components of the ate complexes 5 and 6, are also reported. In addition, the 1H and 13C NMR spectra of 2, 4, 5, 6, 7, and 8 recorded from solutions in C6D6 are disclosed. © 2008 American Chemical Society.


Publication metadata

Author(s): Clegg W, Garcia-Alvarez J, Garcia-Alvarez P, Graham DV, Harrington RW, Hevia E, Kennedy AR, Mulvey RE, Russo L

Publication type: Article

Publication status: Published

Journal: Organometallics

Year: 2008

Volume: 27

Issue: 11

Pages: 2654-2663

ISSN (print): 0276-7333

ISSN (electronic): 1520-6041

Publisher: American Chemical Society

URL: http://dx.doi.org/10.1021/om8001813

DOI: 10.1021/om8001813


Altmetrics

Altmetrics provided by Altmetric


Share