Synthesis of β-Halofurans

Furans substituted with halogens at the beta carbon, which is less prone to electrophilic reactions compared to an alpha position, are important intermediates for accessing highly substituted furans. The regioselectivity of the introduction of a halogen plays an important role in their preparation. This review summarizes efforts for the synthesis of β-halofurans (but not benzofurans) as sorted by halogen (iodo, bromo, chloro, and fluoro). This article provides general reaction schemes that were confirmed with multiple examples and are sometimes applicable to other halogens, and selected reactions specific to a particular substrate and a halogen.