Nitrosonium Salts

Nitrosonium salts are salts containing nitrosonium ion, NO+. Nitrosonium ion is formed by bonding of nitrogen atom to an oxygen atom with a bond order of 3 and the overall diatomic species bears a positive charge. NOClO4, NOSO4H and NOBF4 are some of the examples of nitrosonium salts.

These nitrosonium salts are used in chemical reactions for several purposes, including as a convenient oxidizing agent since the byproduct, NO, is a gas and can be easily removed from the reaction with the stream of N2, and as a diazotizing agent for aryl amine to give diazonium salts. Since the NO+ ion of nitrosonium salt is isoelectronic with carbon monoxide and its mode of coordination to transition metal is also similar to that of carbon monoxide, these salts are used as a source of NO for the synthesis of metal nitrosyl complexes from metal carbonyl complexes.