Carbanions as Functional Groups and Building Blocks for Novel Reagents, Catalysts and Materials

Carbanionic compounds such as organolithium or Grignard reagents are important organometallic reagents and commonly used in organic synthesis for difficult deprotonation or C-C bond formation reactions. Due to the strongly polarized metal carbon bond these reagents are usually highly reactive and sensitive towards air and moisture and thus must be handled under strictly anhydrous conditions. Owing to this intrinsic reactivity, carbanionic compounds are usually only prepared in situ and scarcely applied beyond their classical use as strong bases or alkylation reagents. Free carbanions without stabilizing metal-carbon inter¬action are usually even more reactive but can be isolated when being stabilized by electron withdrawing groups. These naked carbanions are isoelectronic to simple amines. Yet, whereas amines are applied in various fields of chemistry not only as bases but also as versatile building blocks and functional groups, applications of free carbanions are very limited. This project will change the perspective on carbanionic compounds. By careful molecular design the reactivity of carbanions will be controlled to enable their use as broadly applicable building blocks and functional groups. Experimental and computational methods will provide a fundamental understanding of the electronic structure and its influencing factors, thus allowing for a systematic use of the anionic nature and donor capacity of carbanions to reach properties and reactivities, which are not accessible via conventional strategies. Thus, we will provide a new toolbox for the design of smart anionic reagents and catalysts. The power of this concept will be demonstrated by applying carbanions in different research directions ranging from the stabilization of main group species with unusual electronic properties, to designing new bifunctional catalysts with abundant s- and p-block elements and the generation of versatile weakly coordinating anions.