200 Years of Lithium and 100 Years of Organolithium Chemistry

Abstract

The element lithium has been discovered 200 years ago. Due to its unique properties it has emerged to play a vital role in industry, esp. for energy storage, and lithium‐based products and processes support sustainable technological developments. In addition to the many uses of lithium in its inorganic forms, lithium has a rich organometallic chemistry. The development of organometallic chemistry has been hindered by synthetic problems from the start. When Wilhelm Schlenk developed the basic principles to handle and synthesize air‐ and moisture‐sensitive compounds, the road was open to further developments. After more information was available about the stability and solubility of such compounds, they started to play an essential role in other fields of chemistry as alkyl or aryl transfer reagents.

An η3‐Bound Allyl Ligand on Magnesium in a Mechanochemically Generated Mg/K Allyl Complex

“…In the allyl anion, the negative charge is concentrated on the terminal carbons. [39] This fact, combined with the calcu- 2 ]p rogression noted above,s uggests that the change in allyl hapticity occurs to maintain ar oughly tetrahedral distribution of charge around the Mg. The relevance of these results to the structurally authenticated 1 can be appreciated by viewing the h 3 -bound allyl from ap oint almost perpendicular to the C 3 plane (Figure 8).…”

“…Modern synthetic organic chemistry is inconceivable without organometallic compounds of the s-block metals, anchored by the development of the Grignard reagents (around 1900) [1] and alkyllithiums (1917). [2] Even though there have been spectacular advances that have addressed the limited covalencya nd metal-centered redox chemistry in Group 2c ompounds, [3] ligand developments will probably remain the most direct way to work within the constraints of sblock electronic configurations,a nd these have led, for example,todramatic developments in polymerization, hydrogenation, hydrosilylation, and hydroamination catalysts. [4] A particularly flexible basis for such ligand design is the allyl anion, [C 3 H 5 ] À ,and its substituted derivatives.Incombination with mechanochemical synthesis,w ed escribe both an ew coordination mode for the Mg-allyl bond and the catalytic reactivity of ah eterometallic Mg/K-allyl complex, which demonstrate the still unexhausted variety and utility of the sblock-carbon bond.…”

The Future of Polar Organometallic Chemistry Written in Bio‐Based Solvents and Water

“…Similarly,f or the latter,i ntermolecular hydrogen bonding interactions with water result in self-organisation, bond activation, and thusi nn ew carbon-carbon bond formation. [14b] However, when it comes to highly reactive organometallic compounds of s-block elements (mainly Grignarda nd organolithium reagents), the utilisation of which typically requires strictly anhydrous and aproticv olatile organic solvents and inert atmosphere, [15] the role played by water becomes lessc lear and questionable. Ap erusal of the literature reveals that the deliberate or adventitiousa ddition of stoichiometric or catalytic amountso fw ater in organometallic chemistry sometimes provedt ob ec rucial in redirecting reaction in interesting and unexpected ways, for example, by favouring al ithium/halogen exchange, by speeding up the reactionr ate, or by dramatically increasing the enantiomeric excess in asymmetricr eactions.…”

“…At ah igher water percentage, solvophobic sequestration of water into the nanostructure domain of reline becomes unfavourable, and the DES-water mixture is better described as an aqueous solutiono fD ES components. [42] Although understanding solvent effects in organolithium chemistry has played an instrumental role in the development of novel applicationso ft hese commodity reagents in synthesis, [15] the structures of polar organometallics in DESs and their interactions with the different components of these solvents still remain ab lack box. Thus, advancingt he fundamental knowledge on DES structuring,a nd solvent-reagent interactions will be the key in order to make further progress in the synthetic applicationso fp olar organometallics in theseu nconventional solvents.…”

Trans‐Metal‐Trapping: Concealed Crossover Complexes En Route to Transmetallation?

“…Wilhelm Schlenka nd his assistant Johanna Holtz pioneered organolithium compounds in 1917. [1,2] Te ny ears later Schlenka nd Bergmann employed ethyllithium to lithiate fluorenet og enerate fluorenyl lithium. [3] Organolithium-mediated metallation chemistry wasb orn.…”