To further corroborate the proposed role of catechol, we tried to generate i-BuAl•catecholate (i-BuAlC) by mixing Al(i-Bu)3 with catechol in toluene/xylene. The reaction performed using i-BuAlC gave a quantitative yield as illustrated in Figure . To understand whether the stereochemistry of oxime ether (Z and E) affects the selectivity of this AAPE process. An intramolecular competition experiment employing oxime ether derived from 4-(trifluoromethyl)benzophenone as 1:1 ratio of E/Z mixture was tested. As the acidity of C-H bonds affects regioselectivity of iron(III)-catalyzed deprotonative C-H activation, cyclization product a should be major isomer if the C-H site selectivity is not determined by 5