2-Methyl-6-nitrobenzoic anhydride explained

2-Methyl-6-nitrobenzoic anhydride is an organic acid anhydride also known as the Shiina reagent,^{[1] [2]} having a structure wherein carboxylic acids undergo intermolecular dehydration condensation.It was developed in 2002 by Prof. Isamu Shiina (Tokyo University of Science, Japan).^[3] The compound is often abbreviated MNBA.

Abstract

The reagent is used for synthetic reactions wherein medium- and large-sized lactones are formed from hydroxycarboxylic acids via intramolecular ring closure (Shiina macrolactonization).^{[4] [5]} The reaction proceeds at room temperature under basic or neutral conditions. This reagent can be used not only for macrolactonization but also for esterification, amidation, and peptide coupling.

See also

• Condensation reaction
• Fischer-Speier esterification
• Mitsunobu reaction
• Shiina esterification
• Steglich esterification
• Yamaguchi esterification

External links

• 2-Methyl-6-nitrobenzoic Anhydride (MNBA)
• Enantioselective Total Synthesis of Octalactin A Using Asymmetric Aldol Reactions and a Rapid Lactonization To Form a Medium-Sized Ring
• Total Synthesis of Iejimalide B. An Application of the Shiina Macrolactonization

Notes and References

1. Web site: Named Reagents . https://web.archive.org/web/20170904105636/http://www.ochemonline.com/Named_Reagents . OChemOnline . 2017-09-04 . dead.
2. Yahata, K. . Ye, N. . Iso, K. . Naini, S. R. . Yamashita, S.. Ai, Y. . Kishi, Y.. J. Org. Chem.. 2017. 8792–8807 . 10.1021/acs.joc.7b01283. 28741352 . 82. 17. Unified Synthesis of Right Halves of Halichondrins A–C.
3. Shiina, I. . Ibuka, R. . Kubota, M. . Chem. Lett.. 2002. 286. 10.1246/cl.2002.286. 31. 3. A New Condensation Reaction for the Synthesis of Carboxylic Esters from Nearly Equimolar Amounts of Carboxylic Acids and Alcohols Using 2-Methyl-6-nitrobenzoic Anhydride.
4. Shiina, I. . Kubota, M. . Oshiumi, H. . Hashizume, M. . J. Org. Chem.. 2004 . 1822–30 . 10.1021/jo030367x. 15058924 . 69 . 6 . An Effective Use of Benzoic Anhydride and Its Derivatives for the Synthesis of Carboxylic Esters and Lactones: A Powerful and Convenient Mixed Anhydride Method Promoted by Basic Catalysts.
5. Shiina, I. . . 2014 . 196–233 . 10.1246/bcsj.20130216. 87. 2. An Adventurous Synthetic Journey with MNBA from Its Reaction Chemistry to the Total Synthesis of Natural Products. free.