Pd-Catalyzed Orthogonal Knoevenagel/Perkin Condensation-Decarboxylation-Heck/Suzuki Sequences: Tandem Transformations of Benzaldehydes into Hydroxy-Functionalized Antidiabetic Stilbene-Cinnamoyl Hybrids and Asymmetric Distyrylbenzenes

Tandem reactions that involve chemoselective Knoevenagel/Perkin condensation-decarboxylation-Heck/Suzuki coupling or Heck-aldol sequences have been achieved. This enabled the first concise and efficient synthesis of several important hydroxy-functionalized compound classes, such as stilbene-cinnamoyl hybrids (potent protein tyrosine phosphatase1B inhibitors), cinnamoyl-cinnamic acid hybrids, asymmetric distyrylbenzenes, and biarylstyrenes. Previously reported synthesis require multiple steps and protection/deprotection manipulations.