The present review represents the fantasy of Lewis acid towards the synthesis of THF core. Lewis acid catalyzed/promoted annulation reactions are envisioned to be an effective strategy to architect THFs containing bioactive natural products and pharmaceutically important molecules.

Tetrahydrofurans (THFs) are an important structural unit in numerous biologically active compounds and pharmaceutical molecules. The development of an efficient strategies for THF-based core synthesis has been one of the primary focus in synthetic chemistry, in which Lewis-acid-based approaches are emerging as powerful and versatile methods for the synthesis. The approaches allow highly selective and controlled pathways for cyclization, functionalization and rearrangement in building complex THF-containing molecules. This review highlights recent advances featuring 2017 to 2024 in Lewis acid-mediated and/or catalyzed THF cores synthesis, underlining their importance in natural product synthesis and drug discovery process.