In the presence of catalytic amounts of GaCl3 (10 mol%) and 2,6-di(t-butyl)-4-methylpyridine (10 mol%), five- or six-membered ring ketones possessing α,α′-disubstituents are ethenylated at the α-carbon with triethylsilylethyne at 180 °C. The roles of the base are to inhibit decomposition of the products and to promote protodegallation of the organogallium intermediates.
在催化量的 GaCl3(10 摩尔%)和 2,6-二(叔丁基)-4-甲基吡啶(10 摩尔%)存在下,具有δ,δ′-二取代基的五元或六元环酮在 180 °C 下与三乙基硅基乙炔在δ-碳处发生乙烯基化反应。碱的作用是抑制产物的分解和促进有机镓中间体的原降解。
Selective catalytic synthesis of α-alkylated ketones and β-alkylated secondary alcohols <i>via</i> hydrogen-borrowing
作者:Md. Bakibillah、Sahin Reja、Kaushik Sarkar、Deboshmita Mukherjee、Rajesh Kumar Das
DOI:10.1039/d3nj02295a
日期:——
were shown to be efficient catalysts for α-alkylation of ketones and β-alkylation of secondary alcohols with primary alcohols in the presence of a catalytic amount of the Cp*Ir(III) catalyst and tBuOK in toluene at 110 °C via hydrogen-borrowing and produced substituted ketone products in good to excellent yields. This new C–C bond-formingreaction needs very small amounts of catalyst and base and produces
制备了由吡啶甲酰胺基部分支持的一组三种Ir-( III )配合物。这些络合物被证明是酮的 α-烷基化和仲醇与伯醇的 β-烷基化的有效催化剂,在催化量的 Cp*Ir( III ) 催化剂和t BuOK 的存在下,在甲苯中于 110 °C下通过借氢并以良好至优异的产率生产取代酮产品。这种新的 C-C 键形成反应需要非常少量的催化剂和碱,并且仅产生 H 2 O 作为副产物,使其成为一种有吸引力且环保的方案,可实现酮衍生物的“绿色”合成。