tele Nucleophilic Substitutions of Hydrogen in m-(Trichloromethyl)nitrobenzenes with Cyano and Ester Carbanions
(EN)
Surowiec, M.
(EN)
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας
(EL)
Surowiec, M.
(EN)
Stabilized carbanions of malonates, 2-phenylacetonitrile, or isopropyl 2-phenylacetate add to m-(trichloromethyl)nitrobenzene derivatives to form sigma(H) adducts that lose a chloride ion to give intermediate exo-dichloromethylene nitrocyclohexadienes. These undergo re-aromatization through 1,5-hydrogen shift to yield tele substitution mono adducts. Depending on the stoichiometry of the nitroarene to the carbanion, further addition of the nucleophile to the tele mono adduct can yield a mixture of products that are either double or triple adducts. At low temperature, the ail adducts undergo direct 1,2-addition in competition with chloride ion elimination/1,5-hydrogen shift.
(EN)
