Protocol for Stereoselective Construction of Highly Functionalized Dienyl Sulfonyl Fluoride Warheads.

A pyrrolidine-mediated Knoevenagel-type reaction for highly stereoselective construction of novel α-halo-1,3-dienylsulfonyl fluorides was achieved in up to 100% Z-selectivity and high yields at room temperature from condensation of the readily available aldehydes and halomethanesulfonyl fluorides. This protocol provided a class of unique α-halo-1,3-dienylsulfonyl fluorides with wide scope and excellent functional group compatibility. The α-halo-1,3-dienylsulfonyl fluorides were used as versatile building blocks in sulfur fluoride exchange click chemistry, Suzuki reaction, and Sonogashira reaction for the assembly of highly functionalized dienyl sulfonyl fluoride derivatives to be applied as covalent warheads for the discovery of new drugs.