| Abstract
| - Lithiated aryl carbamates (ArLi) bearing methoxy or fluoro substituents in the meta position are generated from lithium diisopropylamide (LDA) in THF, n-BuOMe, Me2NEt, dimethoxyethane (DME), N,N,N′,N′-tetramethylethylenediamine (TMEDA), N,N,N′,N′-tetramethylcyclohexanediamine (TMCDA), and hexamethylphosphoramide (HMPA). The aryllithiums are shown with 6Li, 13C, and 15N NMR spectroscopies to be monomers, ArLi−LDA mixed dimers, and ArLi−LDA mixed trimers, depending on the choice of solvent. Subsequent Snieckus−Fries rearrangements afford ArOLi−LDA mixed dimers and trimers of the resulting phenolates. Rate studies of the rearrangement implicate mechanisms based on monomers, mixed dimers, and mixed trimers.
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