Silica-supported iridium catalysts have been evaluated in the reactions of HSiR₃ (R  Et, OEt) and Me₃SiO[Si(H)(Me)O]_nSiMe₃ (PS1, n  1; PS50, n ∼ 50) with awide variety of primary alcohols. Catalysts obtained by reaction of IrCl(CO)[Ph₂P(CH₂)₂Si(OEt)₃]₂ with silica are rapidly deactivated in a manner similar to the related homogeneous systems. More active catalysts are obtinaed by treating the silica first with Ph₂P(CH₂)₂Si(OEt)₃ and then with [IrCl(C₈H₁₄)₂]₂. The order reactivity of the silanes is PS50 ⪢ HSi(OEt)₃ > HSiEt3 ⪢ PS1, and that of the alcohols reflects principally the bulk of the organic group. Kinetic analysis indicates two pathways involving iridium bound to the phosphine and directly to the silica. The ²⁹ Si{¹H} NMR spectra of PS50 and the product of its reaction with Ph(CH₂)₂OH are reported.

العنوان

Journal Of Organometallic Chemistry Volume 228, Issue 2, 23 March 1982, Pages 191-201

الناشر

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بلد الناشر

فلسطين

نوع المنشور

Both (Printed and Online)

المجلد

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السنة

1982

الصفحات

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