The thermal transformation in vacuo of the well defined surface organometallic fragments [AlO]xSn(H-C4H9)3 (x = 1, 2) 1 grafted on various partially dehydroxylated aluminas (α, γ, η) has been investigated. The surface reactions were followed by qualitative and quantitative determination of the evolved gases including IR spectroscopy, 13C cross-polarisation magic angle spinning and 119Sn magic angle spinning NMR studies. On all aluminas, comparable transformations of 1 were identified showing that the ratio of octahedral : tetrahedral aluminium sites in the aluminas is not an important parameter. Solvolysis reactions of 1 led to the formation of the surface multigrafted species (AlO)x+zSnBu3-z (x = 1, 2; z = 1, 2, 3), while β-H elimination of but-1-ene followed by reductive elimination led to inorganic tin(II) compounds on the surface of the alumina. These transformations occur at temperatures lower than those observed with ≡SiOSnBu3 grafted on the surface of silica. This is possibly related to the more acidic properties of alumina or to the higher concentration and/or mobility of Al hydroxy groups with respect to Si hydroxy groups.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of the Chemical Society - Faraday Transactions|
|State||Published - Sep 21 1996|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry