| Identification | Back Directory | [Name]
dilithium acetylide | [CAS]
1070-75-3 | [Synonyms]
lithium carbide
Dilithioacetylene
dilithium acetylide
Ethynylenebislithium
1,2-Dilithioacetylene
Ethyne-1,2-diylbislithium | [EINECS(EC#)]
213-980-1 | [Molecular Formula]
C2Li2 | [MOL File]
1070-75-3.mol | [Molecular Weight]
37.9034 |
| Hazard Information | Back Directory | [Chemical Properties]
crystal(s) white powder(s); decomposes in water, evolves acetylene when dissolved in acid [HAW93] | [Uses]
Dilithium Acetylide could be used as dianion and as bistrimethylsilyl derivative finds use in the synthesis of variously substituted alkynes, alkenes, γ-diketones, etc.; preferred over its sodium counterpart in reactions with enolizable carbonyls
| [Preparation]
Lithium carbide, Li2C2, may be prepared by the direct combination of lithium and
carbon at about 1000°C or by the reaction of lithium metal with acetylene in liquid ammonia.
The latter process first yields lithium acetylide, LiC=CH, which decomposes to lithium
carbide. The conversion to the carbide is incomplete, however . A convenient laboratory
preparation of lithium carbide may be carried out by bubbling acetylene into a solution of
n-butyllithium in hexane. The precipitated carbide may be filtered from the reaction
mixture, washed, and dried. Lithium carbide is ionic and yields acetylene on hydrolysis. | [Precautions]
Dilithium Acetylide is highly moisture sensitive; very short exposure to air under good ventilation is allowed. Use of a freshly prepared solution is advised. Use in a fume hood.
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