Copper-Catalyzed Hydroamination of N -Allenylazoles: Access to Amino-Substituted N -Vinylazoles

Luca Alessandro Perego (1, 2) , Rémi Blieck (2) , Julie Michel (3) , Ilaria Ciofini (1) , Laurence Grimaud (2, 4) , Marc Taillefer (3) , Florian Monnier (3)

1 IRCP - Institut de Recherche de Chimie Paris
2 ENS-PSL - École normale supérieure - Paris
3 ICGM - Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier
4 LBM UMR 7203 - Laboratoire des biomolécules

Building on mechanistic studies, the innate capability of azoles to act as a directing group has been exploited to design an efficient and simple procedure for the hydroamination of N-allenylazoles such as 1-allenyl-1H-pyrazole, 1-allenyl-1H-benzimidazole and 1-allenyl-1H-1,2,3-triazole with secondary amines such as morpholine, piperidine and N-methylcyclohexylamine. The reaction proceeds under mild conditions by copper(I) catalysis yielding the corresponding original linear E-allylic amines, e.g., I with total regio- and stereoselectivity. D. Functional Theory (DFT) calcns. offer a mechanistic explanation of the significantly higher reactivity of N-allenyl-(1,2)-azoles compared to their 1,3-analogs as a result of the reaction-enhancing coordination of the pyridine-like nitrogen to the copper center.

Mots clés: Allenes; copper; hydroamination; ho- mogeneous catalysis; reaction mechanisms

Domaines: Chimie organique

Luca Alessandro Perego, Rémi Blieck, Julie Michel, Ilaria Ciofini, Laurence Grimaud, et al.. Copper-Catalyzed Hydroamination of N -Allenylazoles: Access to Amino-Substituted N -Vinylazoles. Advanced Synthesis and Catalysis, 2017, 359 (24), pp.4388-4392. ⟨10.1002/adsc.201700965⟩. ⟨hal-01668716⟩