Piperidino Substituted [1]Borametallocenophanes. Synthesis, Reactivity, and Structure

Abstract

ansa-Metallocenes and related complexes have considerable potential as catalyst precursors in the Ziegler-Natta type olefin polymerization. In the present paper we report about the synthesis of piperidinyl-substituted [1]borametallocenophanes of titanium and zirconium. Furthermore, the first example of a base stabilized alkyl-substituted [1]borazirconocenophane was fully characterized and tested for its properties in the polymerization of ethene.

Synthesis, characterisation and slurry phase ethylene polymerisation of rac-(PhBBI*)ZrCl2 immobilised on modified layered double hydroxides

“…The methyl groups were observed between 15.4 and 23.4 ppm. An 11 B{ 1 H} signal was observed at 73.5 ppm which is at a higher frequency than in the related complexes ( (Me 3 Si) 3 C BBI)ZrCl2 (33.2 ppm)43 and ( C 5 H 10 N BBI)ZrCl2 (38.6 ppm) 44. For ( C 5 H 10 N BBI)ZrCl2, the piperidino group is doubly bonded to the boron atom; however, the large difference between the Ph-and C(SiMe3)3-substituted groups is surprising.…”

“…However, the B−Ph bond length (1.571(31) Å) is significantly longer than the corresponding B−N bond (1.376(2) Å). 44 Contrary to rac-( Figure S3).…”

Borata-Alkene Derived Syntheses of (F5C6)2B-Substituted Bis(indenyl) Group 4 Metal Complexes

“…This is straightforward in the case of, for example, the respective dialkylamino boranes (e.g., R = NMe 2 ), since selective functionalization is greatly facilitated by the mesomeric stabilization of the Lewis acid borane site by the NR 2 substituent. Subsequent deprotonation followed by reaction with a group 4 metal halide reagent or simply treatment with a metal amido complex followed by exchange of the residual metal amido groups for halide by treatment with a chlorosilane then may selectively lead to the respective −[B]–NMe 2 substituted bent-metallocene complexes. , …”