After a brief allusion to the current status of synthetic aromatic chemistry, a tour based on the Directed ortho Metalation (DoM) strategy is provided with selections from recent literature which highlight a) the use of DoM for the regiospecific preparation of polysubstituted aromatics and heteroaromatics; b) the valuable symbiosis of DoM with transition metal catalyzed AraAr cross-coupling protocols; c) the extension of DoM to the Directed remote Metalation (DreM) concept in biaryls, which provides methodologies for the construction of condensed aromatics (fluorenones, phenanthrols) and heterocyclics (thioxanthones, xanthones, acridones, dibenzphosphorinones, dibenzthiepinone dioxides, dibenzoxepinones, dibenzazepinones, dibenzphosphinones); and d) the evolving links of DoM to other modern methodologies with a note on the DoM-Grubbs ring-closing metathesis connection. The presentation is solely methodologically rather than total synthesis oriented; dependable directed metalation groups (DMGs ¼ CONR 2 , OCONR 2 , SONR 2 , NHBoc), new and renewed, are emphasized; p-excessive (furan, thiophene, indole) and p-deficient (pyridine) heterocycle HetDoM chemistry is delineated. While definitely not comprehensive, this account attempts to give a flavor of current anionic aromatic chemistry in synthesis.
10.1Scheme 1. Synthetic approaches to substituted aromatics. 10.2 The DoM Reaction as a Methodological Tool 331 Scheme 3. DoM chemistry generalizations. 10.2 The DoM Reaction as a Methodological Tool 333 Scheme 5. The N-cumyl sulfonamide DMG. Scheme 6. The N-cumyl carbamate DMG. 10.2 The DoM Reaction as a Methodological Tool 335 Scheme 9. The di-tert-butyl phosphine oxide DMG. 10.3 Heteroaromatic Directed ortho Metalation (HetDoM) in Methodological Practice 337