Ligand-Controlled Regiodivergent Hydroalkylation of Pyrrolines
1Laboratory of Inorganic Synthesis and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Federale de Lausanne (EPFL), ISIC-LSCI, BCH 3305, Lausanne, 1015, Switzerland.
Abstract:
Nickel hydride (NiH) catalyzed hydrocarbonation has emerged as an efficient approach to construct new C-C bonds containing at least one C(sp3 ) center. However, the regioselectivity of this reaction is by far dictated by substrates. Described here is a strategy to achieve two different regioselectivites of hydroalkylation of the same substrates by using ligand control. This strategy enables the first regiodivergent hydroalkylation of 3-pyrrolines, yielding both 2- and 3-alkylated pyrrolidines, valuable synthetic intermediates and common motifs in many bioactive molecules. This method demonstrates broad scope and high functional-group tolerance, and can be applied in late-stage functionalizations.
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