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. 2012 Aug 29;53(35):4779-4781.
doi: 10.1016/j.tetlet.2012.06.135.

Benzamide synthesis by direct electrophilic aromatic substitution with cyanoguanidine

Rajasekhar Reddy Naredla  1 , Douglas A Klumpp
Affiliations

Benzamide synthesis by direct electrophilic aromatic substitution with cyanoguanidine

Rajasekhar Reddy Naredla et al. Tetrahedron Lett. .

Abstract

Cyanoguanidine is an inexpensive commodity chemical and it is found to be a useful reagent for the direct Friedel-Crafts carboxamidation of arenes. The reaction works best in an excess of Brønsted superacid, an observation suggesting the involvement of a superelectrophilic intermediate. Theoretical calculations indicate that the most stable diprotonated species involves protonation at the guanidine and cyano nitrogen atoms.

Keywords: Friedel-Crafts; benzamide; carboxamidation; superacid; superelectrophile.

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Figures

Figure 1
Figure 1
Calculated relative energies from optimized structures 17/18 and 19/20 (B3LYP 6-311G** level).
Figure 2
Figure 2
Proposed mechanism for the conversion of 2 to benzamide products.
See this image and copyright information in PMC

References

    1. Bréthous L, Garcia-Delgado N, Schwartz J, Bertrand S, Bertrand D, Reymond J-L. J. Med. Chem. 2012;55(10):4605–4618. - PubMed
    2. Mao W, Ning M, Liu Z, Zhu Q, Leng Y, Zhang A. Bioorg. Med. Chem. 2012;20:2982–2991. - PubMed
    1. Wu X-F, Neumann H, Beller M. Chem. Asian J. 2010;5:2168–2172. - PubMed

    2. and references cited therein.

    1. Gauvreau D, Dolman SJ, Hughes G, O'Shea PD, Davies IW. J. Org. Chem. 2010;75:4078. - PubMed
    2. Effenberger F, Gleiter R. Chem. Ber. 1964;97:472.
    1. Kozyukov VP, Kozyukov Vik. P., Muzovskaya EV, Mironov VF. Zhur. Obs. Khim. 1989;59:1202–1203.
    2. Graf R. German Pat. DE 1010958 (1957)
    1. Raja E, Klumpp DA. Tetrahedron. 2011;67:4494–4497. - PMC - PubMed

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