Substituent effect on organotin Tp* compounds as the Tp* reagent for the preparation of mono Tp* complexes of group 4 - 6 metals (Tp* = tris(3,5-dimethylpyrazol-1-yl)hydroborate)

Toshiyuki Oshiki, Kazushi Mashima, Shin Ichi Kawamura, Kazuhide Tani, Kazuo Kitaura

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

Organotin compounds [Tp*SnCl3-(n)Bu(n)] (2: n = 1; 3: n = 2) having a Tp* ligand (Tp* = tris(3,5-dimethylpyrazol-1-yl)hydroborate) are useful reagents for introducing a Tp* ligand on Group 4 and 5 metals and chromium. The test reactions of these organotin compounds along with [Tp*SnCl3] (1) with ZrCl4, affording a known complex [Tp*ZrCl3] (4), were examined. The reaction rates were in the order 3 > 2 >> 1. This tendency was understood by the average Sn-N(Tp* ligand) bond distance being longer in the order 3 > 2 > 1 as revealed by the crystallographic studies and the orbital interactions between the Tp* ligand and the SnCl3-(n)Bu(n) fragments estimated by the ab initio calculations for 1 - 3. On the basis of the above findings, we applied the compound 3 to prepare Tp* complexes of Group 4 - 6 metals. Reactions of TiCl4 with an equimolar amount of 3 afforded [Tp*TiCl3] (7) in good yields after a simple rinse to remove the resulting tin compound, SnBu2Cl2. [Tp*HfCl3] (8) was prepared in moderate yield by reaction of [HfCl4(THF)2] with 3 under severe conditions. Similarly, the reactions of 3 with a stoichiometric amount of [NbCl4(THF)2] or [NbCl5(OEt)2] and TaCl5 in toluene gave [Tp*NbCl3] (9) and [Tp*TaCl3][TaCl6] (10), respectively. We also applied our synthetic method to prepare Tp* complexes of vanadium, [Tp*VCl2(THF)] (11), [Tp*VCl2(DNAP)] (12) (DMAP = 4-dimethylaminopyridine), and [Tp*VCl2(=NC6H3Me2-2,6)] (13) and those of chromium, [Tp*CrCl2(L)] (14: L = THF; 15: L = H2O; 16: L = DMAP). Some of these Tp* complexes, 4, 8, 12, 13, 15, and 16 were crystallographically characterized to have discrete octahedral geometry containing the facial coordination of the Tp* ligand.

Original languageEnglish
Pages (from-to)1735-1748
Number of pages14
JournalBulletin of the Chemical Society of Japan
Volume73
Issue number8
DOIs
Publication statusPublished - Aug 1 2000
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)

Fingerprint Dive into the research topics of 'Substituent effect on organotin Tp* compounds as the Tp* reagent for the preparation of mono Tp* complexes of group 4 - 6 metals (Tp* = tris(3,5-dimethylpyrazol-1-yl)hydroborate)'. Together they form a unique fingerprint.

  • Cite this