Dehydrogenative polymerization of silanes to polysilanes by zirconocene and hafnocene catalysts. A new polymerization mechanism

Journal Article · Mon Nov 27 04:00:00 UTC 1989 · Journal of the American Chemical Society; (USA)

DOI:https://doi.org/10.1021/ja00202a070· OSTI ID:6725502

Woo, Heegweon; Tilley, T D ^[1]

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1. Univ. of California, San Diego (USA)

Polysilanes, (-SiRR{prime}-){sub n} represent a class of inorganic polymers that have unusual chemical properties and a number of potential applications. Prospects for development of a coordination polymerization route to these polymers have improved dramatically with the recent discovery by Harrod and co-workers that titanocene and zirconocene alkyl derivatives are active catalysts for the dehydrogenative coupling of primary silanes RSiH{sub 3} to linear polysilanes with ca. 10-20 Si atoms (eq 1, Cp = {eta}{sup 5}-C{sub 5}H{sub 5}, M = Ti, Zr){sup 2}. We have found that a number of zirconium and hafnium silyl complexes of the type Cp{prime}{sub 2}M(SiR{sub 3})R{prime} (Cp{prime} = Cp, Cp* ({eta}{sup 5}-C{sub 5}Me{sub 5}); M = Zr, Hf; R = Me, Ph, SiMe{sub 3}; R{prime} = Cl, alkyl, silyl) are catalyst precursors for this dehydrogenative coupling reaction and that polymer molecular weights can vary as a function of reaction conditions and catalyst. This report describes observations that suggest a mechanism for dehydrogenative silane polymerization by zirconocene and hafnocene catalysts.

• OSTI ID: 6725502
• Journal Information: Journal of the American Chemical Society; (USA), Journal Name: Journal of the American Chemical Society; (USA) Vol. 111:20; ISSN 0002-7863; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400200* -- Inorganic
Organic
& Physical Chemistry
CALCULATION METHODS
CATALYSTS
CHEMICAL REACTIONS
COMPLEXES
DATA
DATA ANALYSIS
DEHYDROGENATION
EXPERIMENTAL DATA
HAFNIUM COMPLEXES
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
MEASURING INSTRUMENTS
MEASURING METHODS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
POLYMERIZATION
SILANES
SILICON COMPOUNDS
TRANSITION ELEMENT COMPLEXES
ZIRCONIUM COMPLEXES