Adduct

Source: Wikipedia, the free encyclopedia.
(Redirected from
Addition compound
)

In

reaction product containing all atoms of all components.[1] The resultant is considered a distinct molecular species. Examples include the addition of sodium bisulfite to an aldehyde to give a sulfonate
. It can be considered as a single product resulting from the direct combination of different molecules which comprises all atoms of the reactant molecules.

Adducts often form between

Lewis bases.[2] A good example is the formation of adducts between the Lewis acid borane and the oxygen atom in the Lewis bases, tetrahydrofuran (THF): BH3·O(CH2)4 or diethyl ether: BH3·O(CH3CH2)2. Many Lewis acids and Lewis bases reacting in the gas phase or in non-aqueous solvents to form adducts have been examined in the ECW model. [3] Trimethylborane, trimethyltin chloride and bis(hexafluoroacetylacetonato)copper(II) are examples of Lewis acids that form adducts which exhibit steric effects. For example: trimethyltin chloride, when reacting with diethyl ether, exhibits steric repulsion between the methyl groups on the tin and the ethyl groups on oxygen. But when the Lewis base is tetrahydrofuran, steric repulsion is reduced. The ECW model
can provide a measure of these steric effects.

Ball and stick diagram of the Lewis adduct between BH3 and THF
  • THF molecule
    THF molecule
  • BH3 molecule
    BH3 molecule
  • Lewis adduct between BH3 and THF
    Lewis adduct between BH3 and THF

Compounds or mixtures that cannot form an adduct because of

.

Adducts are not necessarily molecular in nature. A good example from

pi electrons of the gas molecule in the electron-donating role.[4]

Adduct ions

An adduct

mass spectrometer
ion source.

See also

References