Al. Cholli et al., NECESSARY CONDITIONS FOR THE PI-ELECTRON DELOCALIZATION IN ENAMINO-TYPE MUSCLE-RELAXANTS, Journal of pharmaceutical sciences, 82(12), 1993, pp. 1275-1280
Two necessary conditions have been proposed for the pi-electron deloca
lization across four bonds in bis-quaternary bromides of enamino spiro
-ketal-type compounds. Dynamic NMR data analysis of these compounds su
ggests that pi-electron delocalization takes place if the first atom i
s nitrogen and the fourth atom is either nitrogen or oxygen [i.e., N+=
C-C=N (or O)]. The second condition is that the end atoms of the four-
bond system should not be therminal group.