Palladium-Mediated Cyclization of 6-Methyl-1-phenyl-6-hepten-2-one to Form 3-Methyldiphenylmethane: Carbonyl Activation by a Neutral Palladium(II) Complex
摘要:
Reaction of 6-methyl-1-phenyl-6-hepten-2-one (4) with a stoichiometric mixture of PdCl2(CH3CN)(2) (2) and Me3SiCl in dioxane at 70 degrees C formed 3-methyldiphenylmethane (6) in 78% isolated yield. A number of experiments supported a mechanism for the conversion of 4 to 6 initiated by palladium-mediated carbonyl-ene reaction to form the isolable palladium alkene-alcohol complex[GRAPHICS](7) followed by Me3SiCl-mediated dehydration to form the unobserved palladium diene complex[GRAPHICS](II) and palladium-mediated oxidation of II to form 6.