94301-04-9Relevant articles and documents
Waste-minimized synthesis of C2 functionalized quinolines exploiting iron-catalysed C-H activation
Ferlin, Francesco,Zangarelli, Agnese,Lilli, Simone,Santoro, Stefano,Vaccaro, Luigi
, p. 490 - 495 (2021)
Herein we present an efficient and regioselective iron-catalyzed methodology for the external oxidant-free functionalization of quinoline-N-oxides. The protocol, based on the use of inexpensive and easily accessible FeSO4, showed broad applicability to a wide range of substrates. An additional green feature of this synthetic methodology is H2O being the only by-product. Experimental and computational investigations provide support to a mechanism based on a facile C-H activation event. The green efficiency of the process has also been carefully assessed using: (i) metrics related to the synthetic process (AE, Yield, 1/SF, MRP and RME); (ii) safety/hazard metrics (SHZI and SHI); and (iii) metrics related to the metal used as the catalyst (Abundance, OEL and ADP). In addition to the many advantages of this protocol related to the green iron catalyst used and the safety/hazard features of the process, an E-factor value of ca. 0.92 (84 to >99% reduction compared to known protocols) evidently confirms the sustainable efficiency of the procedure presented. Practical utility has also been demonstrated by performing the reaction efficiently on a multi-gram scale. This journal is
Synthesis of (E)-2-Alkenylazaarenes via Dehydrogenative Coupling of (Hetero)aryl-fused 2-Alkylcyclic Amines and Aldehydes with a Cobalt Nanocatalyst
Zhou, Changjian,Tan, Zhenda,Jiang, Huanfeng,Zhang, Min
, p. 2887 - 2892 (2018/05/03)
To date, the synthesis of (E)-2-alkenylazaarenes via the condensation of 2-methyl N-heteroarenes with aldehydes or their equivalents has been well demonstrated. However, the direct formation of such a class of useful compounds from extensively distributed 2-alkylcyclic amine motifs remains an unresolved goal. Herein, by employing the nitrogen-silica-doped carbon (Vulcan XC-72R) as the support, we have developed a low-loading cobalt nanocatalyst (Co/N-Si-C). The combination of such a catalyst with p-nitrobenzoic acid and molecular O2 exhibits excellent catalytic performance towards the dehydrogenative coupling of (hetero)aryl-fused 2-alkylcyclic amines with aldehydes to afford the (E)-2-alkenylazaarenes. In the reaction, effective capture of the partially dehydrogenated cyclic amine motifs appears to be the key strategy to address the issue of the chemoselectivity. The developed catalytic transformation proceeds with the merits of broad substrate scope, good functional group tolerance, high atom-efficiency, use of an earth-abundant and reusable cobalt catalyst and molecular O2 as a green oxidant, which offers an important basis for the direct conversion of inert cyclic amine units into the functional frameworks.
