Lithium Triethylborohydride Property

Melting point:

66-67° (Binger); mp 78-83° (dec) (Brown, 1977)

Density 

0.892 g/mL at 25 °C

Flash point:

1 °F

storage temp. 

Flammables + water-Freezer (-20°C)e area

solubility 

Miscible with tetrahydrofuran and benzene.

form 

Liquid

color 

Colorless to light gray

Sensitive 

Air & Moisture Sensitive

Merck 

14,5544

BRN 

4151240

Exposure limits

ACGIH: TWA 50 ppm; STEL 100 ppm (Skin)
OSHA: TWA 200 ppm(590 mg/m3)
NIOSH: IDLH 2000 ppm; TWA 200 ppm(590 mg/m3); STEL 250 ppm(735 mg/m3)

CAS DataBase Reference

22560-16-3(CAS DataBase Reference)

Safety

Hazard Codes 

F,C

Risk Statements 

11-14/15-19-34-40-37

Safety Statements 

16-26-33-36/37/39-43-45

RIDADR 

UN 3399 4.3/PG 1

WGK Germany 

1

F 

10-23

HazardClass 

4.3

PackingGroup 

I

HS Code 

29319090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H225Highly Flammable liquid and vapour

H260In contact with water releases flammable gases which may ignite spontaneously

H302Harmful if swallowed

H314Causes severe skin burns and eye damage

H318Causes serious eye damage

H333May be harmful if inhaled

H335May cause respiratory irritation

H351Suspected of causing cancer

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P223Keep away from any possible contact with water, because of violent reaction and possible flash fire.

P231+P232Handle under inert gas. Protect from moisture.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P370+P378In case of fire: Use … for extinction.

P402+P404Store in a dry place. Store in a closed container.

P403+P235Store in a well-ventilated place. Keep cool.

P405Store locked up.

Lithium Triethylborohydride Chemical Properties,Usage,Production

Description

Lithium triethylborohydride is the organoboron compound with the formula LiEt3BH. Commonly referred to as LiTEBH or Superhydride, it is a powerful reducing agent used in organometallic and organic chemistry. It is a colorless or white liquid but is typically marketed and used as a THF solution. The related reducing agent sodium triethylborohydride is commercially available as toluene solutions.
LiBHEt3 is a stronger reducing agent than lithium borohydride and lithium aluminium hydride.

Chemical Properties

colorless to light grey cloudy solution

Uses

Powerful and selective reducing agent.
As a reducing agentLithium triethylborohydride is used as a powerful reducing agent in organic synthesis for the conversion of carbonyl compounds to alcohols. It is also used in the preparation of alkynyl alcohols from the cleavage of cyclic keto-vinyl triflates. It is also used in the reduction of esters and lactones to alcohol and diol respectively. Further, it is used to prepare 1-methylcyclohexanol and 1,4-butanediol from 1,2-epoxybutane and gamma-butyrolactone respectively. It is also utilized for reductive cleavage of mesylates and tosylates in synthetic organic chemistry.

Uses

LiTEBH can be used as a reagent:

• To reduce alkyl halides to alkanes via dehydrogenation reactions.
• For the selective reduction of epoxides to Markovnikov alcohols.
• To reduce tosylates or mesylates primary alcohols to hydrocarbons.
• For reductive cyclization reactions for the preparation of useful intermediates.
• In the synthesis of hepta(manno-3-deoxy-6-O-t-butyldimethylsilyl)-β-cyclodextrin by reduction of hepta(manno-2,3-anhydro-6-O-t-butyldimethylsilyl)-β-cyclodextrin.
• For hydrodefluorination of C-F bonds using Ni catalyst.
• To prepare alkynyl alcohols from cleavage of cyclic keto-vinyl triflates.
• In the stereoselective reduction of bicyclic imides, isoquinolines, and pyridines.
• To prepare tungsten and molybdenum hydride complexes.

Preparation

LiBHEt3 is prepared by the reaction of lithium hydride (LiH) and triethylborane (Et3B) in tetrahydrofuran (THF):
LiH + Et3B → LiEt3BH
Its THF solutions are stable indefinitely in the absence of moisture and air.

Application

Lithium Triethylborohydride (LiTEBH) is widely used as a powerful and selective reducing agent that shows super hydride activity in organic synthesis.
LiTEBH can be used as a reagent:
To reduce alkyl halides to alkanes via dehydrogenation reactions.
For the selective reduction of epoxides to Markovnikov alcohols.
To reduce tosylates or mesylates primary alcohols to hydrocarbons.
For reductive cyclization reactions for the preparation of useful intermediates.
In the synthesis of hepta(manno-3-deoxy-6-O-t-butyldimethylsilyl)-β-cyclodextrin by reduction of hepta(manno-2,3-anhydro-6-O-t-butyldimethylsilyl)-β-cyclodextrin.
For hydrodefluorination of C-F bonds using Ni catalyst.
To prepare alkynyl alcohols from cleavage of cyclic keto-vinyl triflates.
In the stereoselective reduction of bicyclic imides, isoquinolines, and pyridines.
To prepare tungsten and molybdenum hydride complexes.

General Description

Super-Hydride^? solution (Lithium triethylborohydride or LiTEBH) is widely used as a powerful and selective reducing agent that shows super hydride activity in organic synthesis.

Precautions

Moisture sensitive. Air sensitive. Incompatible with water and strong oxidizing agents.

References

Tamang, S.; Kim, K.; Choi, H.; Kim, Y.; Jeong, S. Synthesis of colloidal InSb nanocrystals via in situ activation of InCl3. Dalton Trans. 2015, 44 (38), 16923-16928.
Kandapallil, B.; Colborn, R. E.; Bonitatibus, P. J.; Johnson, F. Synthesis of high magnetization Fe and FeCo nanoparticles by high temperature chemical reduction. J. Magn. Magn. Mater. 2015, 378, 535-538.