Treatment of dilithium or dipotassium salt of p-tert-butylcalixarene with tBuPCl2 or PhPCl2 produced 1,2-alternate phosphorus-bridged p-tert-butylcalixarene derivatives (tBuPC)H2 (1) and (PhPC)H2 (2), respectively. An X-ray diffraction study of 2 showed that it exists in 1,2-alternate conformation. Reaction of 2 with sulfur gave (PhSPC)H2 (3), which exists in cone conformation. Treatment of TiCl4 with 1-3 produced the corresponding dichlorides L2TiCl2 [L2=tBuPC (5); PhPC (6); and PhSPC (7)]. Reaction of R2Mg·2THF (R=Me or CH2Ph) with (DMSC)TiCl2 (8) yielded (DMSC)TiMe2 (9) and (DMSC)Ti(CH2Ph)2 (10), respectively. Cationic derivatives [(DMSC)Ti(NCCH3)Me2]BArF4 (11) and [(DMSC)Ti(NCCH3)(CH2Ph)]BArF4 (12) were prepared from the respective reactions of 9 and 10 with [Ph3C]BArF4 [ArF=(CF3)2C6H3] in the presence of CH3CN. Similarly, 9 and 10 reacted with [Ph3C]OTf (one equivalent) to yield [(DMSC)Ti(OTf)Me2] (13) and [(DMSC)Ti(OTf)(CH2Ph)] (14), respectively. NMR data showed that the more exposed exo-alkyl was abstracted. Complexes 5-10 and 14 showed modest ethylene polymerization activities at 25°C with 500 molar equivalents of methylalumoxane (MAO) as cocatalyst.
|Number of pages||11|
|Journal||Journal of Organometallic Chemistry|
|State||Published - Sep 5 1999|
Bibliographical noteFunding Information:
Thanks are expressed to the Kentucky National Science Foundation EPSCoR Program (grant number EPS-9452895) for support of this work and to the Chemistry Department of the University of Kentucky for the award of fellowships to O.V.O. The authors also thank Professors Jack Selegue and Mark Meier for helpful discussions.
- Aryloxide ligand
- Calixarene ligand
- Olefin polymerization
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
- Materials Chemistry