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Lithium imide is an inorganic compound with the chemical formula Li 2 N H. This white solid can be formed by a reaction between lithium amide and lithium hydride. [1] LiNH 2 + LiH → Li 2 NH + H 2. The product is light-sensitive and can undergo disproportionation to lithium amide and characteristically red lithium nitride. 2 Li 2 NH → LiNH 2 ...
Lithium amide or lithium azanide is an inorganic compound with the chemical formula LiNH 2. It is a white solid with a tetragonal crystal structure. [1] Lithium amide can be made by treating lithium metal with liquid ammonia: [2] 2 Li + 2 NH 3 → 2 LiNH 2 + H 2. Lithium amide decomposes into ammonia and lithium imide upon heating. [3]
Heating lithium amide with lithium hydride yields lithium imide and hydrogen gas. This reaction takes place as released ammonia reacts with lithium hydride. [2] Heating magnesium amide to about 400 °C yields magnesium imide with the loss of ammonia. Magnesium imide itself decomposes if heated between 455 and 490 °C. [6]
Sample aldol reaction with lithium enolate. Lithium enolate formation can be generalized as an acid–base reaction, in which the relatively acidic proton α to the carbonyl group (pK =20-28 in DMSO) reacts with organolithium base. Generally, strong, non-nucleophilic bases, especially lithium amides such LDA, LiHMDS and LiTMP are used.
The result is a condensation reaction: [5] (RCO) 2 O + R′NH 2 → (RCO) 2 NR′ + H 2 O. These reactions proceed via the intermediacy of amides. The intramolecular reaction of a carboxylic acid with an amide is far faster than the intermolecular reaction, which is rarely observed.
Lithium hydroxide is another important compound that is used in air purification systems, as well as in the production of lithium greases and lubricants. Lithium chloride is used as a desiccant and in the production of lithium metal, while lithium sulfate is used in the production of fertilizers and as a reagent in chemical reactions
Lithium–halogen exchange is a crucial part of Parham cyclization. [15] In this reaction, an aryl halide (usually iodide or bromide) exchanges with organolithium to form a lithiated arene species. If the arene bears a side chain with an electrophillic moiety, the carbanion attached to the lithium will perform intramolecular nucleophilic attack ...
Chiral auxiliaries are incorporated into synthetic routes to control the absolute configuration of stereogenic centers. David A. Evans' synthesis of the macrolide cytovaricin, considered a classic, utilizes oxazolidinone chiral auxiliaries for one asymmetric alkylation reaction and four asymmetric aldol reactions, setting the absolute stereochemistry of nine stereocenters.