is an organic chemical compound
having the chemical formula O
. This heterocycle
, pictured at right, features both amine
and ether functional groups
. Because of the amine, morpholine is a base
; its conjugate acid
is called morpholinium. For example, when morpholine is neutralized by hydrochloric acid
, one obtains the salt
Morpholine may be produced by the dehydration of diethanolamine
with sulfuric acid
Morpholine is a common additive, in ppm concentrations
, for pH
adjustment in both fossil fuel
and nuclear power plant steam
systems. Morpholine is used because its volatility
is about the same as water
, so once it is added to the water, its concentration becomes distributed rather evenly in both the water and steam phases
. Its pH adjusting qualities then become distributed throughout the steam plant to provide corrosion
protection. Morpholine is often used in conjunction with low concentrations of hydrazine
to provide a comprehensive all-volatile treatment chemistry for corrosion protection for the steam systems of such plants. Morpholine decomposes reasonably slowly in the absence of oxygen
even at the high temperatures
in these steam systems.
Morpholine undergoes most chemical reactions
typical for other secondary amines
, though the presence of the ether oxygen withdraws electron density from the nitrogen, rendering it less nucleophilic (and less basic) than structurally similar secondary amines such as piperidine
. For this reason, it forms a stable chloramine (CAS#23328-69-0).
It is commonly used to generate enamines.
Morpholine is widely used in organic synthesis. For example, it is a building block in the preparation of the antibiotic linezolid and the anticancer agent gefitinib (Iressa).
Morpholine is used as a chemical emulsifier in the process of waxing fruit. Fruits make waxes naturally to protect against insects and fungal contamination, but this can be lost by means of the food processing companies when they clean the fruit. As a result, an extremely small amount of new wax is applied and morpholine is then added and used as an emulsifier to evenly coat a fruit with the wax.
In research and in industry, the low cost and polarity of morpholine lead to its common use as a solvent for chemical reactions.
As a component in fungicides
Morpholine derivatives used as agricultural fungicides in cereals are known as ergosterol biosynthesis inhibitors