A Convenient Synthesis of Amidines via Cycloaddition–Decarboxylation of Isocyanates and Nitrones

Abstract

A base-promoted reaction between isocyanates and nitrones has been described, allowing an access to a variety of important functionalized amidines under mild reaction conditions. This strategy provides a convenient, effective, and scalable approach for the direct assembly of amidine compounds from simple starting materials in excellent yields.

Key words

amidines - isocyanates - nitrone - heterocycles - decarboxylation

• References

• 1 Guo W, Zhao M, Tan W, Zheng L, Tao K, Fan X. Org. Chem. Front. 2019; 6: 2120
• 2 Rauws TR. M, Maes BU. W. Chem. Soc. Rev. 2012; 41: 2463
• 3 Quek JY, Davis TP, Lowe AB. Chem. Soc. Rev. 2013; 42: 7326
• 4 Aly AA, Bräse S, Gomaa MA.-M. ARKIVOC 2018; (vi): 85
• 5a Zhou M, Li J, Tian C, Sun X, Zhu X, Cheng Y, An G, Li G. J. Org. Chem. 2019; 84: 1015
• 5b Gao T, Zhao M, Meng X, Li C, Chen B. Synlett 2011; 1281
• 5c Harjani JR, Liang C, Jessop PG. J. Org. Chem. 2011; 76: 1683
• 6a Khalifa MM, Bodner MJ, Berglund JA, Haley MM. Tetrahedron Lett. 2015; 56: 4109
• 6b Wang J, Xu F, Shen Q. Org. Lett. 2008; 10: 445
• 7a Das VK, Thakur AJ. Tetrahedron Lett. 2013; 54: 4164
• 7b Obenauf J, Kretschmer W, Bauer T, Kempe R. Eur. J. Inorg. Chem. 2013; 537
• 7c Stippich K, Kretschmer R, Beckert R, Goerls H. Synthesis 2010; 1311
• 7d Ursini A, Delpogetto M, Guercio G, Perboni A, Rossi T. Synlett 2001; 388
• 8 Zhang W.-X, Nishiura M, Hou Z. Chem. Eur. J. 2007; 13: 4037
• 9a Salva MC, Garvin C, Antilla JC. J. Org. Chem. 2011; 76: 1456
• 9b Musiol HJ, Moroder L. Org. Lett. 2001; 3: 3859
• 10a Liu B, Ning Y, Virelli M, Zanoni G, Anderson EA, Bi X. J. Am. Chem. Soc. 2019; 141: 1593
• 10b Zhang Z, Huang B, Qiao G, Zhu L, Xiao F, Chen F, Fu B, Zhang Z. Angew. Chem. Int. Ed. 2017; 56: 4320
• 10c Kim J, Stahl SS. J. Org. Chem. 2015; 80: 2448
• 10d Schwarz L, Girreser U, Ciement B. Eur. J. Org. Chem. 2014; 1961
• 10e Chen S, Xu Y, Wan X. Org. Lett. 2011; 13: 6152
• 10f Bae I, Han H, Chang S. J. Am. Chem. Soc. 2005; 127: 2038
• 11a Chiacchio MA, Legnani L, Campisi A, Paola B, Giuseppe L, Iannazzo D, Veltri L, Giofrè S, Romeo R. Org. Biomol. Chem. 2019; 17: 4892
• 11b Ritter T, Carreira EM. Angew. Chem. Int. Ed. 2005; 44: 936
• 11c Bell AM. T, Bridges J, Cross R, Falshaw CP, Taylor BF, Taylor GA, Whittaker IC, Begley MJ. J. Chem. Soc., Perkin Trans. 1 1987; 2593
• 11d Ashburn SP, Coates RM. J. Org. Chem. 1985; 50: 3076
• 11e Evans AR, Hafiz M, Taylor GA. J. Chem. Soc., Perkin Trans. 1 1984; 1241
• 11f Damavandy JA, Jones RA. Y. J. Chem. Soc., Perkin Trans. 1 1981; 712
• 11g Safir SR, Lopresti RJ. J. Am. Chem. Soc. 1958; 80: 4921
• 12 Mo D.-L, Pecak WH, Zhao M, Wink DJ, Anderson LL. Org. Lett. 2014; 16: 3696
• 13 Lin J.-P, Zhang F.-H, Long Y.-Q. Org. Lett. 2014; 16: 2822
• 14a Li P, Ma N, Wang Z, Dai Q, Hu C. J. Org. Chem. 2018; 83: 8233
• 14b Liu K, Teng H.-L, Wang C.-J. Org. Lett. 2014; 16: 4508