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Lithium bromide was used as a sedative beginning in the early 1900s, but it fell into disfavor in the 1940s as newer sedatives became available and when some heart patients died after using the salt substitute lithium chloride. [11] Like lithium carbonate and lithium chloride, it was used as treatment for bipolar disorder.
Expressing resonance when drawing Lewis structures may be done either by drawing each of the possible resonance forms and placing double-headed arrows between them or by using dashed lines to represent the partial bonds (although the latter is a good representation of the resonance hybrid which is not, formally speaking, a Lewis structure).
A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).
The lithium bromide forms a complex with the methyllithium. Most commercially available methyllithium consists of this complex. "Low-halide" methyllithium is prepared from methyl chloride. [1] Lithium chloride precipitates from the diethyl ether since it does not form a strong complex with methyllithium. The filtrate consists of fairly pure ...
The dot-and-cross diagram for molecular oxygen in the ground state. The oxygen nuclei are as indicated and the electrons are denoted by either dots or crosses, depending on their relative spins. The above three-dimensional LDQ structures are useful for visualising the molecular structures, but they can be laborious to construct.
Many mechanisms exist reflecting the myriad types of cross-couplings, including those that do not require metal catalysts. [7] Often, however, cross-coupling refers to a metal-catalyzed reaction of a nucleophilic partner with an electrophilic partner. Mechanism proposed for Kumada coupling (L = Ligand, Ar = Aryl).
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 ...
Its conjugate acid has a pK a of ~26, [4] making it is less basic than other lithium bases, such as LDA (pK a of conjugate acid ~36). It is relatively more sterically hindered and hence less nucleophilic than other lithium bases. It can be used to form various organolithium compounds, including acetylides [3] or lithium enolates. [2] where Me ...