Son, A. J. R., Schweiger, S. W., Thorn, M. G., Moses, J. E., Fanwick, P. E., Rothwell, I. P. (April 2003) The isolation and chemistry of tantalum dimethylamides containing resolved 3,3 '-disubstituted-1,1 '-bi-2,2 '-naphthoxide ligands. Dalton Transactions (8). pp. 1620-1627. ISSN 1477-9226
Abstract
Reaction of the tantalum dimethylamide substrates [Ta(NMe2)(5)] or mer,cis-[Ta(NMe2)(2)Cl-3(HNMe2)] with one equivalent of the 3,3'-disubstituted-2,2'-dihydroxy-1,1'-binaphthyl [H2O2C20H10(R)(2)-3,3'] (R = SiMe3, 1; SiMe2Ph, 2; SiMePh2, 3; SiPh3, 4) leads to the series of amine adducts [Ta(O2C20H10R2-3,3')(NHMe2)(NMe2)(3)] (R = SiMe3, 5; SiMe2Ph, 6; SiMePh2, 7; SiPh3, 8) and [Ta(O2C20H10R2-3,3')(NHMe2)(NMe2)Cl-2] (R = SiMe3, 9; SiMe2Ph, 10; SiMePh2, 11; SiPh3, 12). Structural analyses by X-ray diffraction of (S)-5, (R)-7 and (R,S)-8 show a pseudooctahedral geometry about tantalum with the coordinated dimethylamine ligand located cis to the two naphthoxide oxygen atoms. In the case of (S)-9, (R)-10 and (S)-12, the solid-state structure consists of both chloride ligands being located trans to the two naphthoxide oxygen atoms. Solution NMR spectroscopic properties of 5-12 are consistent with an identical structure being adopted in solution with the amine ligands being strongly bound in all cases. When (S)-5 is heated under vacuum the dimethylamine ligand is lost leading to [Ta(O2C20H10{SiMe3}(2)-3,3')(NMe2)(3)] (S)-13. Reaction of (S)-5 with SiCl4 leads to a mixture of [Ta(O2C20H10(SiMe3)(2)-3,3')(NHMe2)Cl-3] (S)-14 and [Ta(O2C20H10-{SiMe3}(2)-3,3')Cl-4][Me2NH2] (S)-15. The solid-state structure of (S)-15 was determined. The amine/ amide ligands in (S)-12 undergo insertion of CS2 leading to the dimethyidithiocarbamate, (S)-[Ta(O2C20H10-3,3'{SiPh3}(2))(CS2NMe2)(2)Cl](S)-16. The solid state structure of (S)-16 consists of a pentagonal bipyramidal geometry about Ta with an axial oxygen and chloride ligand.
| Item Type: | Paper |
|---|---|
| CSHL Authors: | |
| Depositing User: | Matthew Dunn |
| Date: | April 2003 |
| Date Deposited: | 17 Nov 2020 21:32 |
| Last Modified: | 17 Nov 2020 21:32 |
| URI: | https://repository.cshl.edu/id/eprint/39788 |
Actions (login required)
 |
Administrator's edit/view item |