Chiral Ferrocenyl−Iodotriazoles and −Iodotriazoliums as Halogen Bond Donors. Synthesis, Solid State Analysis and Catalytic Properties.

Emmanuel Aubert (1) , Abdelatif Doudouh (1) , Emmanuel Wenger (1) , Barbara Sechi (2) , Paola Peluso (2) , Patrick Pale (3) , Victor Mamane (3)

1 CRM2 - Cristallographie, Résonance Magnétique et Modélisations
2 ICB - Istituto di Chimica Biomolecolare = Institute of Biomolecular Chemistry
3 Institut de Chimie de Strasbourg

Despite the increasing number of applications based on halogen bond (XB), asymmetric catalysis purely based on such supramolecular interactions still remains a huge challenge. The first step toward its development is the design of appropriate XB chiral donor molecules with good catalytic properties. In this context, we report the synthesis of a series of iodinated compounds based on the triazole or triazolium ring and possessing the planar chirality of ferrocene. Their XB donor property was attested by X-ray diffraction analysis, showing short I•••N and I•••F interactions in the triazole-based derivatives and in the tetrafluoroborate salt of a idodotriazolium, respectively. The potential of these compounds to act as XB-based catalysts was demonstrated in the aza-Diels-Alder reaction involving an imine and a diene. Whereas triazole-based derivatives were inactive in this reaction, the triflate salts of iodotriazoliums delivered the expected cycloadduct with high yield.

Domaines: Chimie de coordination; Catalyse; Chimie organique

Emmanuel Aubert, Abdelatif Doudouh, Emmanuel Wenger, Barbara Sechi, Paola Peluso, et al.. Chiral Ferrocenyl−Iodotriazoles and −Iodotriazoliums as Halogen Bond Donors. Synthesis, Solid State Analysis and Catalytic Properties.. European Journal of Inorganic Chemistry, inPress, 2022 (5), pp.e202100927. ⟨10.1002/ejic.202100927⟩. ⟨hal-03550021⟩