The First Example of Samarium Diiodide‐Promoted Intramolecular Ketone—Ester Coupling of Ketones Tethering Acyloxyalkyl Side Chains Producing 2‐Hydroxy Cyclic Hemiacetals.

Abstract

It is demonstrated that reaction of cyclic ketones tethering acyloxyalkyl side chains with SmI2 promotes novel intramolecular addition of samarium ketyl radicals to ester carbonyl resulting in formation of 2-hydroxy cyclic hemiacetals. In some cases, the yield can be improved by addition of tBuOH. -(HASEGAWA*, E.; OKAMOTO, K.; TANIKAWA, N.; NAKAMURA, M.; IWAYA, K.; HOSHI, T.; SUZUKI, T.; Tetrahedron Lett. 47 (2006) 44, 7715-7718; Dep. Chem., Fac. Sci., Niigata Univ., Ikarashi, Niigata 950-21, Japan; Eng.) -Mais 06-103