n-Butyllithium

Description

n-BuLi is a strong base (pKa ~ 50) and is typically sold as a solution in hexanes (1.6M or 2.5M). It reacts violently with water and needs to be stored under an inert atmosphere to prevent its reacting with moisture in the air.

The Uses of n-Butyllithium

n-Butyllithium is used as a polymerization initiator in the production of elastomers like polybutadiene and styrene- butadiene- styrene. As a strong base, it is utilized in the synthesis of organic compounds. It undergoes thermal decomposition to prepare 1-butene.

The Uses of n-Butyllithium

To a solution of the SM (5.56 g, 19.6 mmol) in THF (20 mL) was added LDA (2M in THF/heptane/ethylbenzene, 19.6 mL, 39.2 mmol) dropwise at -78 C. The reaction was stirred at -78 C for 1 h, after which time was added dropwise a solution of Iodine (9.94 g, 39.2 mmol) in THF (10 mL). After 30 min, the dry ice bath was removed and the reaction was warmed to RT. The mixture was quenched by the addition of sat aq Na2S2O3, then extracted with EtOAc. The combined organics were washed with H2O, brine, dried (MgSO4), and concentrated. The resulting material was purified by silica gel chromatography (0-20% EtOAc/hexane) to provide the product as a white solid. [2.65 g, 33%]