Previous transition metal-catalyzed synthesis processes of δ-diketones are plagued by the high cost of the rhodium catalyst and harsh reaction conditions. Herein a low-cost, roomtemperature ruthenium catalytic method is developed based on the coupling of α-keto sulfoxoniumylides with cyclopropanols. The mild protocol features a broad substrate scope (47 examples) and a high product yield (up to 99%)
Stereoselective Iron-Catalyzed Alkylation of Enamides with Cyclopropanols via Oxidative C(sp<sup>2</sup>)–H Functionalization
作者:Xing Zhang、Tian-Ming Yang、Lu-Min Hu、Xu-Hong Hu
DOI:10.1021/acs.orglett.2c03563
日期:2022.12.2
Established herein is a radical-mediated C–H alkylation of enamides with cyclopropanols. An environmentally benign catalytic system with iron salt and air is used to permit the oxidative coupling process. The protocol demonstrates a broad substrate scope, allowing the stereoselective synthesis of alkylated enamides. The value of this strategy is further reflected by late-stage diversification of complex
Pd(0) or Pd(II)-catalyzed ring-opening reactions of benzylidene- and alkylidenecyclopropyl ketones and aldehydes
作者:Xiang-Ying Tang、Min Shi
DOI:10.1016/j.tet.2009.08.044
日期:2009.10
Pd(0) catalyzed reactions of methylenecyclopropyl carbonyl compounds afforded a convenient method for the synthesis of conjugate (E,E)-1,3-diene derivatives 2 in good to excellent yields. Moreover, we also found that Pd(II)-catalyzed reactions of methylenecyclopropyl carbonyl compounds with water gave 1,5-diketones in good to high yields via a carbene-palladium intermediate. The plausible reaction mechanisms have also been provided on the basis of control and O-18-labeling experiments. (c) 2009 Elsevier Ltd. All rights reserved.
2-(<i>N</i>-Methylanilino)-acrylnitril, ein neuer 2-C-Michael-Akzeptor