Synthesis and structures of rac-Me2Si(η5-1-indenyl)2Hf(NMe 2)2 and {Me2Si(η5-1-indenyl)(η 3-2-indenyl)}Hf(NMe2)2

Joseph N. Christopher, Richard F. Jordan, Jeffrey L. Petersen, Victor G. Young

Research output: Contribution to journalArticlepeer-review

36 Scopus citations

Abstract

The amine elimination reaction of Me2Si(1-indenyl)2 (1, (SBI)H2) and Hf(NMe2)4 (2) affords rac-Me2Si(η5-1-indenyl)2Hf(NMe 2)2 (rac-3, rac-(SBI)Hf(NMe2)2) in 20% isolated yield. This reaction proceeds by initial formation of a mono(indenyl) intermediate, (η5-C9H6SiMe2C9H 7)-Hf(NMe2)3 (4), which reacts reversibly with a second equivalent of 2 to form a binuclear complex, {μ-η55-Me2Si(1-indenyl) 2}{Hf(NMe2)3}2 (5), and undergoes reversible intramolecular amine elimination to form rac-3 and meso-3. The novel C1-symmetric ansametallocene {Me2Si(η5-1-indenyl)(η 3-2-indenyl)}Hf(NMe2)2 (6), in which one of the indenyl groups is bridged through the 2-position, is observed as a side product in the synthesis of 3. Complex 6 has been prepared in 21% isolated yield by thermolysis of 4 (or mixtures of 1 and 2) at 160 °C and can be converted to {Me2Si(η5-1-indenyl)(η 3-2-indenyl)}HfMe2 (7, 100% NMR) by reaction with AlMe3. The molecular structures of rac-3 and 6 have been determined by X-ray crystallography.

Original languageEnglish (US)
Pages (from-to)3044-3050
Number of pages7
JournalOrganometallics
Volume16
Issue number13
DOIs
StatePublished - Jun 24 1997

Fingerprint Dive into the research topics of 'Synthesis and structures of rac-Me<sub>2</sub>Si(η<sup>5</sup>-1-indenyl)<sub>2</sub>Hf(NMe <sub>2</sub>)<sub>2</sub> and {Me<sub>2</sub>Si(η<sup>5</sup>-1-indenyl)(η <sup>3</sup>-2-indenyl)}Hf(NMe<sub>2</sub>)<sub>2</sub>'. Together they form a unique fingerprint.

Cite this