Radical C(sp<sup>2</sup>)–H Trifluoromethylation of Aldehydes in Aqueous Solution
作者:Pei Zhang、Haigen Shen、Lin Zhu、Weiguo Cao、Chaozhong Li
DOI:10.1021/acs.orglett.8b03012
日期:2018.11.16
The copper-mediated C(sp2)–H trifluoromethylation of aldehydes is described. The reaction of aldehydes with (bpy)Cu(CF3)3, Et3SiH, and K2S2O8 in aqueous acetone at room temperature provides the corresponding trifluoromethyl ketones in satisfactory yields. The protocol is applicable to both aliphatic and aromatic aldehydes and exhibits a broad substrate scope and wide functional group compatibility
描述了铜介导的醛的C(sp 2)–H三氟甲基化。在室温下,醛与(bpy)Cu(CF 3)3,Et 3 SiH和K 2 S 2 O 8在丙酮水溶液中的反应以令人满意的产率提供了相应的三氟甲基酮。该协议适用于脂族和芳族醛,并具有广泛的底物范围和广泛的官能团相容性。提出了一种涉及Cu(II)介导的酰基三氟甲基化的机理。
Metal-halogen exchange-initiated intramolecular conjugate addition reactions of conjugated acetylenic esters
作者:Manning P. Cooke
DOI:10.1021/jo00076a053
日期:1993.11
The lithium-iodine exchange-initiated intramolecular conjugate addition reactions of some model gamma-iodo-alpha,beta-acetylenic esters have been examined. Product mixtures arising from proton abstraction reactions were observed in reactions leading to 5-membered ring formation. More efficient cyclizations resulted when reactions were conducted in the presence of trimethylsilyl chloride to trap intermediate allenolate ions. Allenolate ion trapping by an internal electrophilic center in 26 resulted in the highly efficient formation of bicyclic ester 27.