Figure describes the substrate scope. The iron-catalyzed system is highly effective for πextended oxime ether substrates. The oxime ether substrates derived from acridinone (2 and 4), xanthenone ( ), thioxanthenone (6), and anthrone (7) all reacted quantitatively resulting annulation 10 products easily purified by silica gel chromatography or recrystallization. The AAPE reaction also works well with spiro-conjugated carbocycles to give a new spiro-conjugated aza-arene (8) in 81% yield. Oxime ether derived from seven-membered-ring dibenzosuberenone yielded the desired product in 86% yield (9) but the five-membered-ring fluorenone failed to react (10), which was attributed to the difference in N=C-C bond angles for ferracycle formation. This difference in C-H activation reactivity was also observed in 15 carbonyl directed C-H methylation . An aza-pyrene framework can be easily constructed from phenalenone (11). AAPE was compatible with flavone and 7,8-benzoflavone producing unprecedented aza-arenes skeletons from these bio-active nature products for possible medicinal applications (17 and 18). The relatively low yield of flavone is ascribed to its competitive decomposition . A variety diaryl acetylenes possessing different substituents with electronic properties, including methoxyl (13, 21, 22), 20 bromide (14), trifluoromethyl (15), and alkyls (19 and 20) all reacted smoothly. Besides tolane derivatives, dialkyl acetylenes are also well compatible (12, 23-26). Notably, methylated aza-arenes can be obtained using 2-butyne in quantitative yield (23). Methylation has proven to be an effective strategy for enhancing not only the efficiency of compounds in medicinal chemistry but also, more recently, in the field of electronic materials science .