Intramolecular S<sub>N</sub>Ar Reactions in a Large-Ring Ketocalix[6]arene

2007-06-07T00:00:00Z (GMT) by Katerina Kogan Silvio E. Biali
Ketocalix[6]arene <b>2e</b> was prepared by CrO<sub>3</sub> oxidation of the methylene groups of <b>2a</b>, followed by hydrolysis of the acetate groups. <b>2e</b> undergoes intramolecular S<sub>N</sub>Ar reactions under the usual methylation conditions (MeI, base), yielding mono- and dixanthone calixarene derivatives.