An organolithium reagent is a carbon nucleophile similar to a Grignard reagent. Preperation of Organolithium reagents is usually achieved by reaction of an organohalogen with lithium metal, i.e. R-X +2Li => R-Li + LiX. Alkyl bromides in particular undergo this reaction with impressive speed. This article needs a complete rewrite for the reasons listed on the talk page. ... A Grignard Reagent is an alkyl- or aryl- magnesium halide. ... General Name, Symbol, Number lithium, Li, 3 Chemical series alkali metals Group, Period, Block 1, 2, s Appearance silvery white/gray Atomic mass 6. ...
Organolithium reagents are used in organic synthesis, and are known under the collective class of organometallic compounds.
The most commonly used organolithium reagents are methyllithium, n-butyllithium, and t-butyllithium. t-butyllithium, or tert-butyllithium is the single strongest base that is commercially available, with a pKa greater than 85. An acid-base reaction is a chemical reaction between an acid and a base. ... In chemistry and biochemistry, acid dissociation constant, the acidity constant, or the acid-ionization constant () is a specific type of equilibrium constant that indicates the extent of dissociation of hydrogen ions from an acid. ...
The addition of a halogenated butyl rubber to the tread formulation of a tire leads to an improvement in the wet skid resistance of the tire tread but there is a concomitant reduction in the wear resistance of the tire tread.
The halogenated butyl rubber onto which is grafted the polymer based on conjugated diolefin monomers is selected from chlorinated butyl rubber and brominated butyl rubber and is preferably a chlorinated butyl rubber having a chlorine content of from about 0.75 to about 1.75 weight percent chlorine based on the chlorinated butyl rubber.
A solution of purified chlorinated butyl rubber (4.8 g) in dry cyclohexane (425 g) under a positive pressure of nitrogen was then transferred to a reaction vessel containing the freshly prepared lithium terminated polybutadiene (16.8 g) in cyclohexane (107.0 g) and the mixture was stirred vigorously at ambient temperature for 16 hours.
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