Iridium-Catalyzed Regio- and Enantioselective <i>N</i>-Allylation of Pyrazoles with Dienyl/Monoallylic Alcohols

Abstract

Here we report the first example of iridium-catalyzed asymmetric N -allylation of pyrazoles with dienyl allylic alcohols under mild conditions with broad functional group tolerance, exhibiting excellent N 1 /C3-site selectivities and enantioselectivities (up to >99% ee). In addition to pyrazoles, other nucleophiles including benzotriazole, triazole, and pyrazole precursors (aryl vinyldiazos) are also suitable in this method. Notably, with the use of Sc(OTf) 3 as additive and reactions performed at 30 °C for 24 h, the N 1 -C5 or N 1 -C1 selective alkylated pyrazoles are also obtained.

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