Reductive metalation of 1,2-diaryl-substituted ethenes: synthetic applications

Reduction of 1,2-diaryl-substituted ethenes with Na metal in dry THF allowed easy access to a variety of 1,2-diaryl-1,2-disodiumethanes. These diorganometallic intermediates were elaborated into the corresponding 1,2-diarylethanes (aqueous work up), or cycloalkylated with 1,3-dichloropropanes. The last reaction led to a highly diastereoselective synthesis of trans-1,2-diaryl-substituted cyclopentanes.