Mechanism and Application of Baker-Venkataraman O→C Acyl Migration Reactions

This literature review focuses on the OC acyl migration of aryl esters to yield the corresponding 1,3-dicarbonyl productsa reaction known as the Baker-Venkataraman rearrangementand outlines their subsequent transformations. The purpose of the review is to highlight the utility of the rearrangement which provides a key step in the synthesis of various heterocyclic motifs. The scope of the Baker-Venkataraman rearrangement is illustrated by way of numerous examples of its application, and in doing so, the review contains over 100 references and covers just over 100 years of the literature, from the first report of the rearrangement by Auwers in 1910 up to more recent examples in the past few years. 1 Introduction 2 Historical Perspective 3 Mechanism 4 Applications: General Routes to Heterocycles 4.1 Flavones and Flavanones 4.2 Xanthones 4.3 Chromones 4.4 Coumarins 4.5 Anthrapyran and Anthracyclin Antibiotics 4.6 Benzopyrans 5 The Retro-Baker-Venkataraman Rearrangement 6 Summary and Outlook