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The Schlosser base (or Lochmann-Schlosser base), the combination of n-butyllithium and potassium tert-butoxide, is commonly cited as a superbase. n -Butyllithium and potassium tert -butoxide form a mixed aggregate of greater reactivity than either component reagent.
A strong base is a basic chemical compound that can remove a proton (H +) from (or deprotonate) a molecule of even a very weak acid (such as water) in an acid–base reaction. Common examples of strong bases include hydroxides of alkali metals and alkaline earth metals, like NaOH and Ca(OH) 2, respectively. Due to their low solubility, some ...
A Lewis base is also a Brønsted–Lowry base, but a Lewis acid does not need to be a Brønsted–Lowry acid. The classification into hard and soft acids and bases ( HSAB theory ) followed in 1963. The strength of Lewis acid-base interactions, as measured by the standard enthalpy of formation of an adduct can be predicted by the Drago–Wayland ...
Lithium tetramethylpiperidide (LiTMP or harpoon base) Other strong non-nucleophilic bases are sodium hydride and potassium hydride. These compounds are dense, salt-like materials that are insoluble and operate by surface reactions. Some reagents are of high basicity (pK a of conjugate acid around 17) but of modest but not negligible ...
According to calculations, ortho-diethynylbenzene dianion is the strongest superbase and has a proton affinity of 1,843.987 kJ/mol (440.723 kcal/mol). [1] The meta isomer is the second-strongest, and the para isomer is the third. All three are readily able to accept any proton to its ethynyl tails, from almost any compound.
In chemistry, the Verkade base (or Verkade superbase) is a powerful superbase with the formula P(MeNCH 2 CH 2) 3 N. A colorless oil, it is an aminophosphine although its inventor John Verkade called it proazaphosphatrane. The trimethyl derivative or 2,5,8,9-tetraaza-1-phosphabicyclo[3.3.3]undecane is the simplest. [1]
Similarly, when ammonia is the solvent, the strongest acid is ammonium (NH 4 +), thus HCl and a super acid exert the same acidifying effect. The same argument applies to bases. In water, OH − is the strongest base. Thus, even though sodium amide (NaNH 2) is an exceptional base (pK a of NH 3 ~ 33), in water it
It was the strongest known base until 2008, when the isomeric diethynylbenzene dianions were determined to have a higher proton affinity. The methanide ion CH − 3 was the strongest known base before lithium monoxide anion was discovered. [2] LiO − has a proton affinity of ~1782 kJ/mol. [3]