R–X +
R –ONa
’
R–O–R + Na X
’
+
–
Ethers containing  substituted alkyl groups (secondary or tertiary)
may also be prepared by this method The reaction involves SN2 attack
of an alkoxide ion on primary alkyl halide Diethyl ether has been
used widely as an
inhalation anaesthetic But due to its slow
effect and an
unpleasant recovery
period, it has been
replaced, as an
anaesthetic, by other
compounds