n-Butyllithium

Other Names:

Butyllithium

n-BuLi

BuLi

General Information:

Structure:

CAS Number: 109-72-8

Molecular Weight: 64.06 g/mol

Appearance: Colorless solution

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.

Common Uses:

Reagent for lithiation (ex. iodination via lithiation)

Procedure excerpt:

. . . flask was cooled in a dry ice/acetone bath for 10 min, the treated dropwise with n-BuLi (1.8M in hexanes, 1.627 mL, 2.93 mmol). After 30 min, a solution of Iodine . . .

[full procedure]

Reagent for lithiation-halogen exchange (ex. formylation via lithium-halogen exchange)

Procedure excerpt:

To a mixture of the SM (200 g, 0.995 mol) in dry THF (1.7 L) at -70 C was added dropwise a solution of nBuLi in hexane (438 mL, 1.09 mol). After stirring . . .

[full procedure]

Strong base for forming Wittig reagents in situ

Procedure excerpt:

n-BuLi (2.6M in hexane, 2.3 mL, 5.94 mmol) was added dropwise to a stirred solution of (methoxymethyl)triphenylphosphonium chloride (2.04 g, 5.94 mmol) in THF . . .

[full procedure]

Safety:

n-Butyllithium is a strong base and is pyrophoric.

References:

1) Patent Reference: WO2014201173, page 366, (19.7 MB)

2) Patent Reference: WO2016014463, page 93, (6.7 MB)

3) Patent Reference: WO2012129344, page 124, (7.3 MB)

4) Patent Reference: WO2015129926, page 71, (21.5 MB)

5) Wikipedia: n-Butyllithium (link)

6) www.sigmaaldrich.com: n-Butyllithium solution (link)

7) Reich, H. J.; Rigby, J. H.; Handbook of Reagents for Organic Synthesis, Acidic and Basic Reagents