( l brace (. eta. sup 5 -C sub 5 Me sub 4 )Me sub 2 Si(. eta. sup 1 -NCMe sub 3 ) r brace (PMe sub 3 )ScH) sub 2 : A unique example of a single-component. alpha. -olefin polymerization catalyst
- California Institute of Technology, Pasadena (USA)
The synthesis and structure of the title compound are described. ({l brace}({eta}{sup 5}-C{sub 5}Me{sub 4})Me{sub 2}Si({eta}{sup 1}-NCMe{sub 3}){r brace}Sc(PMe{sub 3})){sub 2}({mu}-H){sub 2} (3) crystallizes with a molecule of toluene per scandium in the monoclinic system, space group C2/c, with a = 21.238 (3) {angstrom}, b = 11.470 (2) {angstrom}, c = 22.253 (3) {angstrom}, {beta} = 113.16 (1){degree}, V = 4984.0 (14) {angstrom}{sup 3}, Z = 8 (four dimers), and d = 1.24 g{center dot}cm{sup {minus}3}. Propene, 1-butene, and 1-pentene are cleanly, albeit slowly, polymerized with >99% head-to-tail coupling to produce linear, atactic polymers with M{sub n} = 3,000-4,000 and PDI's of 1.7-2.1. Chain transfer is relatively slow and appears to occur by {beta}-H elimination. All evidence points to a one-component catalyst system with all scandium centers functioning alike.
- OSTI ID:
- 6438494
- Journal Information:
- Organometallics; (USA), Vol. 9:3; ISSN 0276-7333
- Country of Publication:
- United States
- Language:
- English
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ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CATALYSTS
SCANDIUM COMPLEXES
CRYSTAL STRUCTURE
SYNTHESIS
DATA ANALYSIS
EXPERIMENTAL DATA
MEASURING INSTRUMENTS
MEASURING METHODS
PETROCHEMISTRY
COMPLEXES
DATA
INFORMATION
NUMERICAL DATA
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties