InCl3 Catalyzed Highly Diastereoselective [3+2] Cycloaddition of 1,2-Cyclopropanated Sugars with Aldehydes: A Straightforward Synthesis of Persubstituted Bis-Tetrahydrofurans and Perhydrofuro[2,3-b]pyrans

A mild and efficient strategy for the construction of persubstituted bis-tetrahydrofuran and perhydrofuro[2,3-b]pyran derivatives has been developed. Persubstituted cyclization products were obtained in good to excellent yields. The [3 + 2] cycloaddition of 1,2-cyclopropanated sugars with aldehydes in the presence of InCl3 is highly diastereoselective.