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。
Carbonylation of Enynes under Hydroformylation Conditions Catalyzed by Rhodium Carbonyl. A New Method for Synthesis of Cyclic Enones
Unexpectedly, cyclopentenone derivatives were obtained in moderate yields together with formylsubstituted dienes and unsaturated lactones. This reaction offers a newmethod for the catalytic synthesis of cyclopentenones. A mechanism for the cyclic carbonylation of enynes is also discussed.
Taming Highly Unstable Radical Anions and 1,4-Organodilithiums by Flow Microreactors: Controlled Reductive Dimerization of Styrenes
作者:Yiyuan Jiang、Hideki Yorimitsu
DOI:10.1021/jacsau.2c00375
日期:2022.11.28
dimerization, and the resulting 1,4-organodilithiums are trapped with various electrophiles. Trapping with divalent electrophiles affords precursors for useful yet less accessible cyclic structures, for example, siloles from dichlorosilanes. Thus, we highlight the power of single-electron reduction of unsaturated compounds in flowmicroreactors for organic synthesis.