Synthesis 2021; 53(06): 1087-1094
DOI: 10.1055/s-0040-1705997
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Michael Addition of Indoles to Enones Catalyzed by a Cationic Iron Salt

Tsukasa Inishi
,
Goki Hirata
,
Financial support provided by Yamaguchi University and Japan Society for the Promotion of Science [JSPS, KAKENHI Grant Number JP18H04262(TN), Precisely Designed Catalysts with Customized Scaffolding] is gratefully acknowledged.


Abstract

Indoles are one of the most valuable nucleophiles in Michael additions catalyzed by a proper Lewis acid. In this paper, we found that a cationic iron salt is effective to carry out the Michael addition of indoles. β-Mono- and disubstituted enones reacted smoothly with indoles under our conditions. The cationic iron catalyst is very active, and the maximum TON was up to 425. Moreover, cationic iron-catalyzed conditions enabled a chemoselective Michael addition of a substrate possessing both enone and α,β-unsaturated ester moieties.

Supporting Information



Publication History

Received: 04 November 2020

Accepted after revision: 16 November 2020

Publication Date:
07 January 2021 (online)

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  • References

    • 1a Moore RE, Cheuk C, Patterson GM. L. J. Am. Chem. Soc. 1984; 106: 6456
    • 1b Gribble GW. J. Chem. Soc., Perkin Trans. 1 2000; 1045
  • 2 Manabe K, Aoyama N, Kobayashi S. Adv. Synth. Catal. 2001; 343: 174
    • 3a Liu L, Ma H, Xiao Y, Du F, Qin Z, Li N, Fu B. Chem. Commun. 2012; 48: 9281
    • 3b Yadav JS, Reddy BV. S, Baishya G, Reddy KV, Narsaiah AV. Tetrahedron 2005; 61: 9541
  • 4 Huang Z.-H, Zou J.-P, Jiang W.-Q. Tetrahedron Lett. 2006; 47: 7965
  • 5 Dyker G, Muth E, Hashmi AS. K, Ding L. Adv. Synth. Catal. 2003; 345: 1247
  • 6 Huang G, Sun H, Qiu X, Shen Y, Jiang J, Wang L. J. Organomet. Chem. 2011; 696: 2949
  • 7 Bandini M, Fagioli M, Garavelli M, Melloni A, Trigari V, Umani-Ronchi A. J. Org. Chem. 2004; 69: 7511
  • 8 Shi M, Cui S.-C, Li Q.-J. Tetrahedron 2004; 60: 6679
    • 9a Bandini M, Cozzi PG, Giacomini M, Melchiorre P, Selva S, Umani-Ronchi A. J. Org. Chem. 2002; 67: 3700
    • 9b Ranu BC, Dey SS, Samanta S. ARKIVOC 2005; (iii): 44
  • 10 Swetha A, Raghavender M, Reddy B, Babu M, Meshram HM. Tetrahedron Lett. 2017; 58: 4427
  • 11 Srivastava N, Banik BK. J. Org. Chem. 2003; 68: 2109
  • 12 An L.-T, Zou J.-P, Zhang L.-L, Zhang Y. Tetrahedron Lett. 2007; 48: 4297
  • 13 Zolfigol MA, Veisi H, Mohanazadeh F, Sedrpoushan A. J. Heterocycl. Chem. 2011; 48: 977
    • 14a Nishikata T, Yamamoto Y, Miyaura N. Angew. Chem. Int. Ed. 2003; 42: 2768
    • 14b Nishikata T, Yamamoto Y, Miyaura N. Organometallics 2004; 23: 4317
  • 15 Nishikata T, Yamamoto Y, Miyaura N. Chem. Lett. 2003; 32: 752
  • 16 Nishikata T, Yamamoto Y, Miyaura N. Chem. Commun. 2004; 1822
  • 17 Bauer I, Knölker H.-J. Chem. Rev. 2015; 115: 3170
  • 18 Itoh T, Uehara H, Ogiso K, Nomura S, Hayase S, Kawatsura M. Chem. Lett. 2007; 36: 50
    • 19a Wang X, Zhang Y, Xiao X, Li X. Chem. Lett. 2008; 37: 1284
    • 19b Gao Y.-H, Yang L, Zhou W, Xu L.-W, Xia C.-G. Appl. Organomet. Chem. 2009; 23: 114
    • 19c Veisi H, Maleki B, Eshbala FH, Veisi H, Masti R, Ashrafi SS, Baghayeri M. RSC Adv. 2014; 4: 30683
  • 20 Allgauer DS, Jangra H, Asahara H, Li Z, Chen Q, Zipse H, Ofial AR, Mayr H. J. Am. Chem. Soc. 2017; 139: 13318
  • 21 Liang D, Li X, Zhang W, Li Y, Zhang M, Cheng P. Tetrahedron Lett. 2016; 57: 1027