Previous failures to isolate the oximes of di-omethyl substituted acetophenones-have been summarized by Kadesch.'s2 These are attributed to the difficulty of supplying correctly the additional energy necessary for the conversion of the aceto grouping to the a-oximinoethyl grouping (-C= NOHCH3) in hindered structure^.'^^ In this conversion the a-oximinoethyl grouping is tilted out of the plane of the ring to a greater degree than the aceto grouping ...
