Straight and versatile synthesis of substituted perhydrofuro[2,3-b]pyrans from 2-chloromethyl-3-(2-methoxyethoxy)propene

Direct Synthesis of Bicyclic Acetals via Visible Light Catalysis

Polysubstituted bicyclic acetals are a class of privileged pharmacophores with a unique 3D structure and an adjacent pair of hydrogen bond acceptors. The key, fused acetal functionality is often assembled, via intramolecular cyclization, from linear substrates that are not readily available. Herein, we report a formal cycloaddition between cinnamyl alcohols and cyclic enol ethers under ambient photoredox catalysis conditions. Polysubstituted bicyclic acetals can be prepared in one step from readily available building blocks. Employment of sugar-derived enol ethers allows easy access to a library of scaffolds with intriguing conformation and medicinal chemistry potential.

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Synergistic catalysis of photocatalyst and HAT reagent

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5/5, 5/6, 5/7, 6/6 bicyclic acetals and polysubstituted THF formed in one step

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High stability of bicyclic acetal in SIF and SGF

A neighboring group participation strategy: direct and highly diastereoselective synthesis of 2-substituted and 2,2-bisubstituted perhydrofuro[2,3-b]pyran derivatives

A highly diastereoselective synthesis method for 2-substituted and 2,2-bisubstituted perhydrofuro[2,3-b]pyran derivatives from 2-C-branched sugars via a neighboring group participation strategy was developed.

Efficient Synthesis of Fused Perhydrofuro[2,3-b]pyrans (and Furans) by Ring Opening of 1,2-Cyclopropanated Sugar Derivatives

[structure: see text]. An efficient method has been developed for the construction of fused perhydrofuro[2,3-b]pyrans by diastereoselective ring opening of 1,2-cyclopropanated sugar derivatives. The methodology has been successfully applied to the synthesis of fused perhydrofuro[2,3-b]pyrano-gamma-butyrolactone derivatives.