Formation and decomposition of C3 metallacycles from ethylene and methylene on MoAl alloy thin films.
نویسندگان
چکیده
The reaction between adsorbed ethylene and methylene species has been investigated on a molybdenum-aluminum alloy grown from Mo(CO)(6) on a planar alumina film formed on a Mo(100) single crystal in ultrahigh vacuum. Di-sigma-bonded ethylene reacts with carbene species, formed on the surface from methylene iodide, to form a C(3) metallacycle. This predominantly decomposes to yield propylene, while a smaller portion yields cross-metathesis products since (12)C(13)CH(4) is formed from reaction between (13)C(2)H(4) and (12)CH(2). This work demonstrates for the first time that the reaction proceeds in heterogeneous phase via a C(3) metallacycle as proposed in the Hérisson-Chauvin mechanism.
منابع مشابه
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 128 21 شماره
صفحات -
تاریخ انتشار 2006