RESUMEN
The enantioselective intermolecular sp(3) C-H functionalization at the allylic and benzylic positions was achieved using rhodium-catalyzed reactions with 4-phenyl-N-(methanesulfonyl)-1,2,3-triazole. The optimum dirhodium tetracarboxylate catalyst for these reactions was Rh2(S-NTTL)4. The rhodium-bound α-imino carbene intermediates preferentially reacted with tertiary over primary C-H bonds in good yields and moderate levels of enantioselectivity (66-82% ee). This work demonstrates that N-sulfonyltriazoles can be applied to the effective C-H functionalization at sp(3) C-H bonds of substrates containing additional functionality.
Asunto(s)
Derivados del Benceno/síntesis química , Ácidos Sulfínicos/química , Triazoles/química , Catálisis , Estructura Molecular , Rodio/química , EstereoisomerismoRESUMEN
We herein report the synthesis of a bis-2-pyridylidene palladium(II) complex as an isoelectronic structure of the well-known 2,2'-bipyridine complexes. One-pot or stepwise C-Cl oxidative addition followed by base-mediated C-H palladation of the chlorobipyridine dication to palladium(0) yielded the bis-2-pyridylidene palladium(II) carbonate smoothly.