Efficient Phenolic Oxidations to Construct ortho-Spirolactone Structures Using Oxo-Bridged Hypervalent Iodine(III) Compound
摘要:
The intramoleular ortho-spirocyclization of naphthols 1 bearing carboxylic acid moieties as internal nucleophiles using hypervalent iodine reagents is described. The use of the mu-oxo-bridged hypervalent iodine(III) compound is remarkably effective for this transformation, and spirolactones 2 were obtained in good to excellent yields using the mu-oxo-bis[trifluoroacetato(phenyl)iodine] 4 [PhI(OCOCF(3))O(OCOCF(3))IPh].