Organogel delivery vehicles for the stabilization of organolithium reagents

Abstract

Organolithium reagents are a vital tool in modern organic chemistry, enabling the synthesis of carbon–carbon bonds. However, due to their high reactivity, low temperatures, inert atmospheres and strictly dried solvents are usually necessary for their use. Here we report an encapsulating method for the stabilization of sensitive organolithium reagents—PhLi, n-BuLi and s-BuLi—in a low-cost hexatriacontane (C36H74) organogel. The use of this technology is showcased in nucleophilic addition reactions under ambient conditions, low-temperature bromine–lithium exchange, ortho-lithiation and C–H functionalization. The gel substantially enhances organolithium stability, allows simple storage, handling and delivery, and enables reproducible reagent portioning. The use of gels as easily divided delivery vehicles for hazardous organometallics has the potential to transform this area of synthetic chemistry, making these powerful reactions safer and more accessible to non-specialist researchers, and enabling the more widespread use of these common synthetic methods. [Figure not available: see fulltext.]