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In the method developed by Yamaguchi, hydroxycarboxylic acids (“seco-acids”) are converted into reactive acid anhydrides using 2,4,6-trichlorobenzoyl chloride and the intramolecular esterification is promoted by DMAP under high dilution conditions. This reaction often requires refluxing temperatures depending on the size of the ring being formed.
・Inanaga, J.; Hirata, K.; Saeki, H.; Katsuki, T.; Yamaguchi, M. Bull. Chem. Soc. Jpn. 1979, 52, 1989. DOI: 10.1246/bcsj.52.1989
・Kawanami, Y.; Dainobu, Y.; Inanaga, J.; Katsuki, T.; Yamaguchi, M. Bull. Chem. Soc. Jpn. 1981, 54, 943. DOI: 10.1246/bcsj.54.943
The acid anhydrides react regioselectively due to the steric hindrance by the ortho-substitution on the benzoyl group (Ref: Org. Lett.2006, 8, 47.).
The Yamaguchi conditions are compatible with a wide range of substrates and are used frequently even today. An example shown below is the esterification between two large fragments in the total synthesis of cryptophycin-24.
 Eggen, M.; Mossman, C. J. et al. J. Org. Chem. 2000, 65, 7792. DOI: 10.1021/jo000767+