Treating the benzyl protected 3‐hydroxy‐1,3‐bis(2‐hydroxyphenyl)prop‐2‐en‐1‐ones solely with PhI(OAc)2 (PIDA) in DCE at room temperature readily furnished the seldom studied spiro‐2,2′‐benzo[b]furan‐3,3′‐ones in satisfactory to excellent yields. The hypervalent iodine reagent enables the metal‐free cascade spirocyclization resulting in the dual oxidative C−O bond formation.
在室温下仅用PhI(OAc)2(
PIDA)在室温下仅用PhI(OAc)2(
PIDA)处理苄基保护的3-羟基-1,3-双(2-羟基苯基)丙-2-烯-1-酮很容易提供很少研究的spiro-2 ,2'-苯并[b]
呋喃-3,3'-
酮类产品具有令人满意的优异收率。高价
碘试剂可实现无
金属级联螺环化,从而形成双氧化C-O键。