Metallocene-based Novel Lewis-Pairs; synthesis, coordination behavior, molecular activation

Basic data for this project

Description

Molecular systems which allow for cooperation of subunits exhibiting complementary features are very attractive for modern chemistry. In this regards, phosphine chemistry has recently experienced much progress by its association with formally Lewis-inverted partners such as boranes (FLPs, frustrated Lewispairs). Additionally, organometallic metallocene backbones present a unique sandwich geometry with both rigid and flexible components, and may serve as a tuneable platform to develop innovative cooperative chemistry. In the present project is envisioned the synthesis of novel metallocene-based Lewis-pairs from two complementary approaches. Based on the metallocene chemistry mastered at the Institute of Molecular Chemistry in Dijon, titanocene, zirconocene and ferrocene frameworks will be incorporated either as structuring platform of [phosphine/borane] Lewis-pairs, or as electrophilic partner for [phosphine/metallocenium] ambiphilic compounds. Polyphosphines based on metallocene backbone are targeted for the preparation of intra- and intermolecular polyphosphine/boranes with controlled conformation. The new compounds synthesized will be studied for their coordination chemistry with late transition metals at the Laboratory of Fundamental and Applied Heterochemistry in Toulouse. In particular ambiphilic coordination behaviour towards groups 9 to 11 transition metals, and Z-ligand character of the species will be thoroughly examined The reactivity of these new systems will be mainly investigated at the Organic Chemistry Institute in Münster. A detailed program focused on the properties of the novel metallocene-based Lewis-pairs (MLPs) in the activation of three specific targets is envisioned: (i) their addition to small unsaturated substrates (R-NO, diynes, azides), (ii) their behaviour towards H2 splitting or storing, (iii) their influence on the course of alkene polymerization. The present project represents a promising match between the research interests and experience of the participating research groups. The partners are eager to intensively collaborate on this challenging topic in the emerging field of Lewis-pairs chemistry within the framework of ANR/DFG call.