A ONE-STEP SYNTHESIS OF 2,3-DIHYDRO-1,4-BENZOTHIAZINES AND PHENOTHIAZINES FROM 1,3-THIAZOLIDINE DERIVATIVES OF CYCLOHEXANONES

Article abstract of DOI:10.3987/COM-93-6379

N-Acetyl-1,3-thiazolidine derivatives of cyclohexanones, when treated with a threefold excess N-bromosuccinimide in anhydrous chloroform at room temperature, smoothly afford N-acetyl-2,3-dihydro-1,4-benzothiazines.This represents the first general route to such heterocyclic system in one step from aliphatic precursors.The synthesis optically active N-acetyl-2,3-dihydro-1,4-benzothiazines is also reported.