817587-72-7Relevant academic research and scientific papers
Electrochemical synthesis of dimerizing and nondimerizing orthoquinone monoketals
Deffieux, Denis,Fabre, Isabelle,Titz, Alexander,Leger, Jean-Michel,Quideau, Stephane
, p. 8731 - 8738 (2004)
Anodic oxidation of appropriately substituted 2-methoxyphenols or α-(2-methoxyphenoxy)-2-methylpropionic acids in the presence of methanol furnishes stable orthoquinone monoketals, and thus constitutes a valuable alternative to the use of chemical oxidants that are often based on toxic metallic species. The propionic acid derivatives are initially converted into O-spirolactonic quinone bisketals that are then selectively hydrolyzed into the desired monoketal compounds. In the absence of blocking substituents, orthoquinone monoketals spontaneously undergo Diels-Alder dimerizations into tricyclododecadienedienones with extraordinary site selectivity, regioselectivity, and stereoselectivity. Suggestions are made to open up a new track for a long awaited rationalization of these controls on the basis of the intramolecular [2 + 2] reactivity of these orthoquinone monoketal-derived cyclodimers.
