Nitrosylchlorid

Nitrosyl chloride, with the chemical formula NOCl, is an inorganic compound formed by a nitrosyl group attached to chlorine. The molecule is typically described as a volatile, reactive species and is usually encountered as a gas or in solution in nonaqueous media. It is highly reactive and readily interacts with moisture in air or water.

Preparation and occurrence

Nitrosyl chloride can be prepared by the direct reaction of nitric oxide with chlorine:

2 NO + Cl2 → 2 NOCl.

This synthesis produces NOCl as a reactive gas, which can be condensed or dissolved in suitable solvents under controlled conditions.

Reactivity and properties

NOCl reacts readily with water, undergoing hydrolysis to yield nitrous acid and hydrogen chloride:

NOCl + H2O → HNO2 + HCl.

Nitrous acid (HNO2) is itself unstable and tends to decompose to various nitrogen oxides. NOCl is also reactive toward many organic substrates and other reagents, making it useful as a nitrosylating agent in synthesis, but requiring careful handling.

Applications

In organic synthesis, NOCl serves as a source of the nitrosyl group for introducing nitroso functionality into substrates. It is used to prepare other nitroso compounds and to generate nitrosylating reagents under controlled conditions. Its reactivity allows it to participate in reactions that form nitroso derivatives from amines and related compounds.

Safety and handling

Nitrosyl chloride is toxic and corrosive. It is a lachrymator and irritant that can release toxic nitrogen oxides and chlorine-containing species on decomposition or hydrolysis. It should be stored and handled under strictly dry, inert, and well-ventilated conditions, in containers designed to minimize moisture contact. Appropriate protective equipment and fume hood use are essential.