Cyclopentadienyl nickel nitrosyl is a highly toxic organonickel chemical. In its pure form, it is a diamagnetic, volatile, relatively air-stable liquid with a blood-red color. It has been reported to be the simplest mono-

cyclopentadienyl Cyclopentadienyl can refer to *Cyclopentadienyl anion, or cyclopentadienide, **Cyclopentadienyl ligand *Cyclopentadienyl radical, • *Cyclopentadienyl cation, See also *Pentadienyl In organic chemistry, pentadienyl refers to the organic radic ...

metal complex. The chemical was discovered in 1954 by a team at The International Nickel Company. The molecular formula is ( C₅ H₅) Ni N O. It can be prepared by treating nickelocene with nitric acid.
/ref> It is extremely toxic (T+), and is considered to be one of the most poisonous Organometallic chemistry, organometallic chemicals ever developed. Its toxicity is said to be comparable to

nickel tetracarbonyl Nickel carbonyl (IUPAC name: tetracarbonylnickel) is a nickel(0) organometallic compound with the formula Ni(CO)4. This colorless liquid is the principal carbonyl of nickel. It is an intermediate in the Mond process for producing very high-pur ...

. Due to its high toxicity, cyclopentadienyl nickel nitrosyl has very limited usage. It was patented as a

fuel additive Petrol additives increase petrol's octane rating or act as corrosion inhibitors or lubricants, thus allowing the use of higher compression ratios for greater efficiency and power. Types of additives include metal deactivators, corrosion inhibitors, ...

and anti-caking agent, but it was never used for these purposes due to the health hazards it posed. In the past, it was also studied for its spectroscopic qualities, and saw limited use as a catalyst in organic chemical reactions, but it has since been discounted in favor of less toxic compounds.

Notes

Cyclopentadienyl complexes Organonickel compounds Half sandwich compounds {{organic-compound-stub