n-Butyllithium
[CAS# 109-72-8]

Identification

• Classification: Organic raw materials >> Amino compound >> Acyclic monoamines, polyamines and their derivatives and salts
• Name: n-Butyllithium
• Synonyms: Butyl lithium
• Molecular Formula: C₄H₉Li
• Molecular Weight: 64.05
• CAS Registry Number: 109-72-8
• EC Number: 203-698-7
• SMILES: [Li+].CCC[CH2-]

Properties

• Density: 0.68
• Boiling point: 60-80 °C
• Flash point: -21 °C
• Water solubility: vigorous reaction

Safety Data

• Hazard Symbols: GHS02;GHS05;GHS07 Danger
• Risk Statements: H250-H260-H302-H314-H317-H318
• Safety Statements: P210-P222-P223-P231-P231+P232-P233-P260-P261-P264-P264+P265-P270-P272-P280-P301+P317-P301+P330+P331-P302+P335+P334-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P330-P333+P317-P362+P364-P363-P370+P378-P402+P404-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin corrosion	Skin Corr.	1B	H314
Substances or mixtures which in contact with water emit flammable gases	Water-react.	1	H260
Serious eye damage	Eye Dam.	1	H318
Pyrophoric liquids	Pyr. Liq.	1	H250
Pyrophoric solids	Pyr. Sol.	1	H250
Skin sensitization	Skin Sens.	1	H317
Acute toxicity	Acute Tox.	4	H302
Flammable liquids	Flam. Liq.	2	H225
Self-heating substances or mixtures	Self-heat.	2	H252
Acute toxicity	Acute Tox.	4	H332
Aspiration hazard	Asp. Tox.	1	H304
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Substances or mixtures which in contact with water emit flammable gases	Water-react.	2	H261
Specific target organ toxicity - single exposure	STOT SE	3	H336
Reproductive toxicity	Repr.	2	H361f
Skin corrosion	Skin Corr.	1A	H314
Skin corrosion	Skin Corr.	1	H314
Reproductive toxicity	Repr.	2	H361

• Transport Information: UN 2445

Discovery and Applications

n-Butyllithium (n-BuLi) was first synthesized in the early 20th century as part of ongoing research into organolithium compounds, which began with the discovery of ethyllithium by Karl Ziegler in 1936. Researchers were exploring new reagents that could serve as strong bases and nucleophiles in organic synthesis. The discovery of n-BuLi marked a significant milestone due to its high reactivity and utility in various chemical transformations.

n-BuLi is extensively used as a strong base and nucleophile in organic synthesis. It is crucial for deprotonation reactions, facilitating the formation of carbanions that act as intermediates in the synthesis of complex organic molecules.

In polymer chemistry, n-BuLi is employed as an initiator for anionic polymerization. It helps in the synthesis of polymers with precise molecular weights and narrow molecular weight distributions. This is particularly important for producing specialized polymers like styrene-butadiene rubber (SBR) and thermoplastic elastomers, which are used in tires, adhesives, and various plastic products.

n-BuLi is a precursor for the synthesis of a wide range of organolithium compounds. These derivatives are used as reagents and intermediates in various chemical reactions. For instance, lithium diisopropylamide (LDA), a strong non-nucleophilic base, is prepared using n-BuLi and is widely used in organic synthesis for enolate formation.

n-BuLi is instrumental in metallation reactions, where it is used to introduce lithium into organic molecules. This process, known as lithiation, is key in the synthesis of organometallic compounds and in functionalizing aromatic and heteroaromatic compounds. These metallated intermediates are essential in the pharmaceutical industry for drug development and in materials science for creating advanced materials.

n-BuLi is used in the synthesis of complex drug molecules, enabling the formation of carbon-carbon and carbon-heteroatom bonds that are critical for constructing biologically active compounds.

Beyond pharmaceuticals, n-BuLi is used in the production of fine chemicals, which are high-purity chemical substances used in various applications such as electronics, agriculture, and manufacturing. Its role in creating specific molecular structures makes it a vital reagent in these industries.

References

2024. Synthesis and organocatalytical evaluation of optically pure inherently chiral calix[4]arene phosphoric acids. Journal of Inclusion Phenomena and Macrocyclic Chemistry.
DOI: 10.1007/s10847-024-01267-9

2024. Preparative scalable method for the synthesis of cyclic and acyclic acetals of chloropropiolaldehyde and their transformation into acetals of lithiumpropiolaldehyde. Russian Chemical Bulletin.
DOI: 10.1007/s11172-024-4428-y

2009. Synthesis of brassinolide and its biosynthetic precursors using methyl-3-hydroxy-2-methylpropionate. Bioorganicheskaia khimiia.
DOI: 10.1134/s1068162009020137