کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
61822 47607 2011 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Monoalkylations with alcohols by a cascade reaction on bifunctional solid catalysts: Reaction kinetics and mechanism
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Monoalkylations with alcohols by a cascade reaction on bifunctional solid catalysts: Reaction kinetics and mechanism
چکیده انگلیسی

A bifunctional catalytic system formed by Pd on MgO catalyzes the cascade process between benzyl alcohol and phenylacetonitrile, diethylmalonate and nitromethane, to give the respective α-monoalkylated products without external supply of hydrogen. The process involves a series of three cascade reactions occurring on different catalytic sites. The alcohol undergoes oxidation to the corresponding aldehyde with the simultaneous formation of a metal hydride; then, the aldehyde reacts with a nucleophile formed “in situ” to give an alkene, and finally, the hydrogen from the hydride is transferred to the alkene to give a new C–C bond.A kinetic study on the α-monoalkylation reaction of benzylacetonitrile with benzyl alcohol reveals that the rate-controlling step for the one-pot reaction sequence is the hydrogen transfer reaction from the surface hydrides to the olefin, and consequently, the global reaction rate is improved when decreasing the size of the Pd metal particle.

Pd-MgO catalyzes the α-monoalkylation of activated methylenic compounds with alcohols through a cascade process without external supply of hydrogen. A kinetic study shows that the rate controlling step for the one-pot sequence is the hydrogenation of the olefin by the surface metal hydrides.Figure optionsDownload high-quality image (69 K)Download as PowerPoint slideResearch highlights
► Metal–based bifunctional solids catalyze monoalkylations reactions with alcohols.
► The sequential process is based on hydrogen transfer methodology.
► The rate-controlling step is the hydrogen transfer reaction from the surface hydrides to the olefin.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Catalysis - Volume 279, Issue 2, 25 April 2011, Pages 319–327
نویسندگان
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