Pd-Catalyzed Coupling of N-Tosylhydrazones with Benzylic Phosphates: Toward the Synthesis of Di- or Tri-Substituted Alkenes

This study shows that various di-and tri-substituted alkenes with high chemoselectivity were obtained in good to high yields by coupling N-tosylhydrazones (NTHs) with benzylic phosphates as electrophilic partners. The obtained new catalytic system consisted of PdCl2(CH3CN)(2)/dppp, LiOtBu as a base, and cyclopentyl methyl ether as a green solvent. In addition, we performed a gram-scale transformation using NTH derivatives and benzylic phosphates having a C sp(2)-Cl bond. The latter was used as a starting point for further postfunctionalization of the key intermediates.

Automated summary

This study demonstrates the successful synthesis of various di- and tri-substituted alkenes with high chemoselectivity using N-tosylhydrazones and benzylic phosphates as electrophilic partners. The new catalytic system consisting of PdCl2(CH3CN)(2)/dppp, LiOtBu, and cyclopentyl methyl ether as the solvent exhibits good yields. Furthermore, gram-scale transformations and subsequent postfunctionalization of key intermediates are also reported in this study.