Bis(η 5-cyclopentadienyl)- and bis(η 5-indenyl)metallacycles of titanium and zirconium from methylenecyclopropanes by oxidative coupling

• Published in: Journal of organometallic chemistry Vol. 656; no. 1; pp. 288 - 298
• Main Authors: Binger, Paul, Müller, Patrik, Podubrin, Stefan, Albus, Stefan, Krüger, Carl
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.08.2002
• Subjects: [2+2] and [3+2] Cycloadditions; Bis(η 5-indenyl)zirconium complexes; Methylenecyclopropane; Titanocene(II) and zirconocene(II) complexes; [2+2] and [3+2] Cycloadditions; Titanocene(II) and zirconocene(II) complexes; Methylenecyclopropane; Bis(η 5-indenyl)zirconium complexes
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/S0022-328X(02)01472-9

Methylenecyclopropane ( 1a) reacts with bis(trimethylphosphane)titanocene ( 8) and (η 2-1-butene)(trimethylphosphane)zirconocene ( 12a) via olefin complexes; e.g. 9, in a [2+2] cycloaddition to afford the metallacyclopentane derivates 10, 13 and 14. In contrast, a [3+2] cycloaddition reaction is observed with bis(η 5-lndenyl)(η 2-1-butene)(trimethylphosphane)zirconium ( 12b) to furnish the 1-zircona-4-methylenecyclohexane 15. Similarly, reactions of the complexes 8 and 12a with benzylidenecyclopropane ( 1c) give the olefin complexes 9c and 20, while a direct reaction between the indenyl complex 12b with 1c occurs to furnish the 1-zircona-2-benzylidenecyclobutane complex 21b which was characterised by X-ray crystallography. Methylenecyclopropane ( 1a) reacts with bis(trimethylphosphane)titanocene ( 8) and (η 2-1-butene)(trimethylphosphane)zirconocene ( 12a) via olefin complexes; e.g. 9, in a [2+2] cycloaddition to afford the metallacyclopentane derivates 10, 13 and 14. In contrast, a [3+2] cycloaddition reaction is observed with bis(η 5-lndenyl)(η 2-1-butene)(trimethylphosphane)zirconium ( 12b) to furnish the 1-zircona-4-methylenecyclohexane 15. Similarly, reactions of the complexes 8 and 12a with benzylidenecyclopropane ( 1c) give the olefin complexes 9c and 20, while a direct reaction between the indenyl complex 12b with 1c occurs to furnish the 1-zircona-2-benzylidenecyclobutane complex 21b which was characterised by X-ray crystallography.