Pechmann Condensation

H. v. Pechmann, C. Duisberg, Ber. 16, 2119 (1883).

Synthesis of coumarins by condensation of phenols with β-keto esters in the presence of Lewis acid catalysts:



Early reviews: S. Sethna, Chem. Rev. 36, 10 (1945); S. Sethna, R. Phadke, Org. React. 7, 1 (1953). T. Kappe, E. Ziegler, Org. Prep. Proced. 1, 61 (1969); T. Kappe, C. Mayer, Synthesis 1981, 524; A. G. Osborne, Tetrahedron 37, 2021 (1981); D. H. Hau et al., Synlett. 1990, 233; T-S. Li et al., J. Chem. Res. 1998, 39. Modified conditions: J. E. T. Corrie, J. Chem. Soc. Perkin Trans. I 1990, 2151; D. H. Hua et al., J. Org. Chem. 57, 399 (1992). Cf. Bischler-Napieralski Reaction; Simonis Chromone Cyclization.