Electrochemical generation and reaction of o-quinodimethanes from {[[2-(2,2-dibutyl-2-stannahexyl)phenyl]-methyl]thio}benzenes

The anodic oxidation of {[[2-(2,2-dibutyl-2-stannahexyl)phenyl]methyl]thio} benzenes gave o-quinodimethanes which were trapped in situ by dienophiles t o give the corresponding cycloadducts in excellent yields. The electron tra nsfer and succeeding 1,4-elimination reaction was efficiently completed in a solution of lithium perchlorate/nitromethane in the presence of acetic ac id. The reaction progress was quantitatively controlled by the passage of c harge. By using this new method, an aryltetralin lignan skeleton was also s ynthesized.