Microwave Smiles rearrangement

One of the most commonly encountered applications of Smiles rearrangements in synthesis is to prepare fused aromatic systems via three-step cascades displaying two nucleophilic substitutions with a Smiles rearrangement in between. These sequences have been adapted into more conplex three-conponent couplings such as the benzothiazine synthesis shown in Scheme 19.9. hi this process, 19 reacts first with acyl chloride 18 leading to 20 after substitution with 17. Heating the mixture under microwave conditions tri ers the Smiles rearrangement and the final Sj Ar toward 21. 

The Smiles rearrangement also proceeds under microwave conditions and has been shown to provide a facile C-N bond formation and a one-pot synthesis of arylamines (13) and derivatives (Figure 18.1) [6]. 

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