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It is an amidine base used in organic synthesis. A related compound with related functions is 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The relatively complex nature of the formal names for DBU and DBN (hence the common use of acronyms) reflects the fact that these compounds are bicyclic and contain several functional groups.
1,5-Diazabicyclo(4.3.0)non-5-ene (DBN) - comparable to DBU; 2,6-Di-tert-butylpyridine, a weak non-nucleophilic base [2] pK a = 3.58; Phosphazene bases, such as t-Bu-P 4 [3] Non-nucleophilic bases of high strength are usually anions. For these species, the pK a s of the conjugate acids are around 35–40. Lithium diisopropylamide (LDA), pK a = 36
As a reagent in organic chemistry, DBU is used as a ligand and base. As a base, protonation occurs at the imine nitrogen. [5] Lewis acids also attach to the same nitrogen. [6] These properties recommend DBU for use as a catalyst, for example as a curing agent for epoxy resins and polyurethane.
Tetramethylguanidine is mainly used as a strong, non-nucleophilic base for alkylations, often as a substitute for the more expensive DBU and DBN. [3] Since it is highly water-soluble, it is easily removed from mixtures in organic solvents. It is also used as a base-catalyst in the production of polyurethane. [4]
Strong bases are leveling solvents for acids, weak bases are differentiating solvents for acids. In a leveling solvent, many acids are completely dissociated and are thus of the same strength. All acids tend to become indistinguishable in strength when dissolved in strongly basic solvents owing to the greater affinity of strong bases for protons.
Pages in category "Non-nucleophilic bases" The following 26 pages are in this category, out of 26 total. This list may not reflect recent changes. ...
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 ...
As a strong base, TBD fully deprotonates most phenols, carboxylic acids, and some carbon acids. [7] It catalyzes a variety of reactions including Michael reactions , Henry reactions , transesterification reactions, and Knoevenagel condensations .