Oxalic Acid: A Very Useful Brønsted Acid in Organic Synthesis

Introduction

The title compound oxalic acid is available in anhydrous and dihydrate forms and exhibits several features which have made it particularly attractive as a reagent in organic synthesis. Oxalic acid is a mild Brønsted acid, which finds application in the Beckmann reaction, [1] protection and deprotection of carbonyl compounds, [2-4] and various selective cleavage and hydrolytic reactions. It is frequently used as a mild acidic quench for a variety of reactions including oxidations. [5] Oxalic acid has also been used as an acidic agent in a number of condensation processes such as conden­sation of allylic alcohols with aromatic rings, [6] carbonyl compounds and hydrazines, [7] aromatic amines and aldehydes, [8] and it has been utilized as a bifunctional condensation partner in the synthesis of heterocyclic systems. [9]

Oxalic acid is the simplest of the dicarboxylic acids and is widely used in inorganic chemistry as a precipitant and chelating agent (oxalate as a bidentate ligand has been of great interest in coordination chemistry). [10]

References

• 1 Chandrasekhar S. Gopalaiah K. Tetrahedron Lett.  2003,  44:  7437 
• 2a Andersen NH. Uh H.-S. Synth. Commun.  1973,  3:  125 
• 2b Smith AB. Empfield JR. Vaccaro HA. Tetrahedron Lett.  1989,  30:  7325 
• 2c Caine D. Venkataramu SD. Kois A. J. Org. Chem.  1992,  57:  2960 
• 2d Ziegler FE. Becker MR. J. Org. Chem.  1990,  55:  2800 
• 3a Pearson WH. Poon Y.-F. Tetrahedron Lett.  1989,  30:  6661 
• 3b Mitani K. Yoshida T. Morikawa K. Iwanaga Y. Koshinaka E. Kato H. Ito Y. Chem. Pharm. Bull.  1988,  36:  367 
• 3c Huet F. Lechevallier A. Pellet M. Conia JM. Synthesis  1978,  63 
• 4a Martin VA. Murray DH. Pratt NE. Zhao Y.-b. Albizati KF. J. Am. Chem. Soc.  1990,  112:  6965 
• 4b Avery MA. Chong WKM. Detre G. Tetrahedron Lett.  1990,  31:  1799 
• 5a Apparao S. Schmidt RR. Synthesis  1987,  896 
• 5b Liu H.-J. Nyangulu JM. Synth. Commun.  1989,  19:  3407 
• 6 Fieser LF. J. Am. Chem. Soc.  1939,  61:  3467 
• 7 Paquette LA. Wang T.-Z. Vo NH. J. Am. Chem. Soc.  1993,  115:  1676 
• 8 Peesapati V. Pauson PL. Pethrick RA. J. Chem. Res., Synop.  1987,  194 
• 9 Eweiss NF. Bahajaj AA. J. Heterocycl. Chem.  1987,  24:  1173 
• 10a Krishnamurty KV. Harris GM. Chem. Rev.  1961,  61:  213 
• 10b Kim D.-J. Kroeger DM. J. Mater. Sci.  1993,  28:  4744 
• 11a Burn D. Petrow V. J. Chem. Soc.  1962,  364 
• 11b Weinstein B. Fenselau AH. J. Org. Chem.  1965,  30:  3209 
• 12 Boeckman RK. Walters MA. Koyano H. Tetrahedron Lett.  1989,  30:  4787 
• 13a Demyttenaere J. Syngel KV. Markusse AP. Vervisch S. Debenedetti S. Kimpe ND. Tetrahedron  2002,  58:  2163 
• 13b Carlin RB. Constantine DA. J. Am. Chem. Soc.  1947,  69:  50 
• 13c Miller RE. Nord FF. J. Org. Chem.  1950,  15:  89 
• 14a Bartlett PA. Meadows JD. Ottow E. J. Am. Chem. Soc.  1984,  106:  5304 
• 14b Lygo B. O’Connor N. Tetrahedron Lett.  1987,  28:  3597 
• 15a Comins DL. Abdullah AH. Mantlo NB. Tetrahedron Lett.  1984,  25:  4867 
• 15b Comins DL. Hong H. J. Am. Chem. Soc.  1991,  113:  6672 
• 16 Giles M. Hadley MS. Gallagher T. J. Chem. Soc., Chem. Commun.  1990,  1047