Illuminating the Unexpected Benzylic Carbon−Carbon Bond Cleavage of Arylated Ethanes with Di-n-Butylzirconium Diethoxide by Illumination: Transfer Epizirconation as Exclusively a Photochemical Process1

Abstract

The interaction between 1,1,2,2-tetraphenylethane and di-n-butylzirconium diethoxide (1:2 ratio) in THF at 25 °C does not occur in the dark but does proceed under ambient light (>300 nm). Supplemental illumination, especially in the presence of catalytic amounts of iron salts (e.g., Fe(acac)3 or FeCl3), can lead quantitatively to Ph2CH−Zr(OEt)2−CHPh2, which with H2O (D2O) provides Ph2CH2 (Ph2CHD), and to 1,8-octanediol with some 1-butanol from cleavage of THF.