DIAZABICYCLOALKANES WITH NITROGEN ATOMS IN BRIDGEHEAD POSITIONS. 17. EFFECT OF SUBSTITUENTS IN BENZO-1,4-DIAZABICYCLOOCTENE ON PROTON AFFINITY AND OPENING BY CHLOROFORMATE ESTER

Article abstract of DOI:10.1007/BF00472391

The reaction of benzo<1',2'-b>-1,4-diazabicyclo<2.2.2>octene with chloroformate ester is accompanied by opening of the diazabicyclo fragment and addition of chloroformate ester.A nitro group in the 4' position lowers the rate constant for opening by 40 times in comparison to the unsubstituted heterocycle, while a 4' methoxy group practically does not affect the reaction rate.The ratio of the 6- and 7- substituted 1-(β-chloroethyl)-4-ethoxycarbonyl-1,2,3,4-tetrahydroquinoxalines which are formed agrees with a quantum chemical calculation of the proton affinity and indicates a principally inductive effect of the substituents on the reactivity of the heteroatoms.