Stereospecific Benzyne‐Induced Olefination from β‐Amino Alcohols and Its Application to the Total Synthesis of (−)‐1‐Deoxy‐ D ‐fructose

'Ole in one! Treatment of β-amino alcohols with CS2 under alkaline conditions gave 1,3-thiazolidine-2-thiones, which were then treated with benzyne generated in situ. The reaction underwent an unprecedented addition–elimination process to give the desired olefins in 60–87 % yields (see scheme; DBU=1,8-diazabicyclo[5.4.0]undec-7-ene).