Trifluoroacetic Acid-Promoted Synthesis of 3-Hydroxy, 3-Amino and Spirooxindoles from α-Keto-N-Anilides
摘要:
Ketoanilides containing alkyl side chains were readily cyclized to 3-hydroxy-2-oxindoles or spirooxindoles by a single or double intramolecular Friedel-Crafts reaction in the presence of trifluoroacetic acid (TFA) at room temperature or at 45 degrees C. alpha-Iminocarboxamides, generated in situ from ketoamides, cyclized similarly to 3-aminooxindoles under identical conditions,
Oxygen‐Involved Oxidative Deacetylation of α‐Substituted β‐Acetyl Amides – Synthesis of α‐Keto Amides
摘要:
Abstractα‐Substituted β‐acetyl amides could undergo CC bond cleavage to form α‐keto amides when treated with copper(II) chloride (CuCl2) and boron trifluoride diethyl etherate (BF3⋅OEt2) under an oxygen atmosphere. The yield can be increased by the addition of tert‐butyl hydroperoxide which alone can also effect the reaction. The reaction provides a new protocol for the synthesis of α‐keto amides.magnified image