Aza-ortho-xylylenes in Organic Synthesis

Synthesis of quinolines and acridines by the reaction of 2-(perfluoroalkyl)anilines with lithium and Grignard reagents

“…It is the adduct 10 that undergoes intramolecular 6π-electron cyclization, as evidenced by the isolation and characterization of intermediate 4,4-disubstituted-3,4-dihydroquinoline [30]. The two methodologies discussed above are quite general in scope, and a large array of other substituted quinolines [29,[32][33][34][35][36][37][38] and fused quinolines including acridines [39,40] can easily be prepared by the reaction of 2 or 7 with various basic/nucleophilic reagents [41][42][43][44][45].…”

Five‐Membered Heterocycles: 1,2‐Azoles. Part 2. Isoxazoles and Isothiazoles

“…The nitro derivatives are prepared in higher yields and under milder conditions (Scheme 9.74) [283]. Such compounds are used as precursors of aza-ortho-quinodimethanes (see Scheme 9.119 The key feature of these heterocycles is that they possess the typical properties of an aromatic system but contain a weak nitrogen-oxygen bond, which, under certain reaction conditions, particularly in reducing or basic conditions, is a potential site of ring cleavage.…”

“…2,1-Benzisothiazole 2,2-dioxides 184 can be prepared from a wide range of precursors (Scheme 9.73) [283]. The nitro derivatives are prepared in higher yields and under milder conditions (Scheme 9.74) [283].…”

Benzazetines and their derivatives (review)

“…It was shown that the formation of some products of this reaction (aldimines) is possible as a result both of migration of a hydrogen atom in the initially formed aza-ortho-xylylenes and of the participation of the corresponding benzazetines. Reviews have been devoted to the generation of aza-ortho-xylylenes and their reactions [8,9].…”