N-Cumyl Benzamide, Sulfonamide, and Aryl O-Carbamate Directed Metalation Groups. Mild Hydrolytic Lability for Facile Manipulation of Directed Ortho Metalation Derived Aromatics

N-Cumyl benzamide (2), sulfonamide (8), and O-carbamate (11) compounds undergo directed ortho metalation under standard conditions to give, after quench with a variety of electrophiles, the substituted products 3, 9, and 12, respectively. Regiospecific and convenient approaches to phthalimides (7), 1,2-benzisothiazole 1,1-dioxides (10b), and ortho-substituted phenols (13a) and salicylamides (13b) are thereby established. The mild deprotection protocol for these new cumyl directed metalation groups (DMGs) suggests that they will supersede previous corresponding groups for synthetic anionic aromatic chemistry.