Pd–NHC (NHC = N-Heterocyclic Carbene)-Catalyzed B-Alkyl Suzuki Cross-Coupling of 2-Pyridyl Ammonium Salts by N–C Activation: Application to the Discovery of Agrochemical Molecular Hybrids
natural products, pharmaceuticals, and agrochemicals. Herein, we report the first B-alkyl Suzukicross-coupling of 2-pyridyl ammonium salts to access functionalized 2-alkylpyridines. The use of well-defined, operationally simple Pd-NHCs permits for an exceptionally broad scope of the challenging B-alkyl C–N cross-coupling with organoboranes containing β-hydrogen, representing a novel method for the discovery
Solution and Gas-Phase Investigations of Trimethylsilylpropyl-Substituted Pyridinium Ions. Manifestation of the Silicon δ Effect
作者:Asimo Karnezis、Richard A. J. O’Hair、Jonathan M. White
DOI:10.1021/om200510a
日期:2011.11.14
propylpyridinium ions 15a (M = Si), 15b (M = Ge), 15c (M = Sn), and 15d (M = Pb) and N-methyl-4-trimethyl-M-propylpyridinium ions 16a (M = Si), 16b (M = Ge), 16c (M = Sn), and 16d (M = Pb) provide evidence for a significant through-bond (double hyperconjugative) interaction between the M–CH2 bond and the low-lying π* orbital of the pyridiniumion. The strength of this interaction increases in the order