Highly Regio- and Diastereoselective [3+2] Cycloadditions

Significance

The substituted tetrahydrofuran moiety can be found in a number of natural products possessing interesting biological properties. Quite a few reports describe 2,5-cis-diastereo­selective [3+2] cycloadditions of 2-substituted ­cyclopropane-1,1-diesters with aldehydes. In this work, trans-2,3-disubstituted cyclopropane-1,1-diesters are considered as substrates. While common 2,5-cis-products were obtained with electron-neutral and -poor aromatic aldehydes, electron-rich analogues furnished 2,5-trans-­adducts with excellent diastereoselectivities.