Development of Isomerization and Cycloisomerization with Use of a Ruthenium Hydride with <i>N</i>-Heterocyclic Carbene and Its Application to the Synthesis of Heterocycles
ruthenium hydride complex with N-heterocyclic carbene (NHC) ligand was efficiently generated from the reaction of a second-generation Grubbs ruthenium catalyst with vinyloxytrimethylsilane and unambiguously characterized. This ruthenium hydride complex showed high catalytic activity for the selective isomerization of terminal olefin and for the cycloisomerization of 1,6-dienes. These reactions of N-allyl-o-vinylaniline
第二代Grubbs钌催化剂与乙烯基氧基三甲基硅烷的反应可有效生成具有N-杂环卡宾(NHC)配体的纯氢化钌络合物,并具有明确的特征。该氢化钌络合物对末端烯烃的选择性异构化和1,6-二烯的环异构化显示出高催化活性。的这些反应Ñ -allyl- Ò -vinylaniline导致新的合成方法杂环如吲哚和3-亚甲基-2,3- dihydroindoles,这对于生物活性天然产物有用的合成子。这些程序解决了面向多样性的综合中的一个重要问题。
Synthesis of 1,2-Dihydroquinolines via Hydrazine-Catalyzed Ring-Closing Carbonyl-Olefin Metathesis
作者:Yunfei Zhang、Jae Hun Sim、Samantha N. MacMillan、Tristan H. Lambert
DOI:10.1021/acs.orglett.0c02116
日期:2020.8.7
The synthesis of 1,2-dihydroquinolines by the hydrazine-catalyzed ring-closing carbonyl-olefin metathesis (RCCOM) of N-prenylated 2-aminobenzaldehydes is reported. Substrates with a variety of substitution patterns are shown. With an acid-labile protecting group on the nitrogen atom, in situ deprotection and autoxidation furnish quinoline. In comparison with related oxygen-containing substrates, the