 | |
| Names | |
|---|---|
| IUPAC name Oxidoazaniumylidynemethane | |
| Identifiers | |
| |
3D model (JSmol) | |
| 1071209 | |
| ChEBI | |
| ChEMBL | |
| ChemSpider |
|
| 772 | |
| |
| |
| Properties | |
| HCNO | |
| Molar mass | 43.02 g mol−1 |
| Conjugate base | Fulminate |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Fulminic acid is anacid with the formula HCNO, more specificallyH−C≡N+−O−. It is anisomer ofisocyanic acid (H−N=C=O) and of its elusivetautomer,cyanic acid (H−O−C≡N), and also of isofulminic acid (H−O−N+≡C−).[1]
Fulminate is theanion[C−≡N+−O−] of any of itssalts. For historical reasons, the fulminatefunctional group is understood to be−O−N+≡C− as in isofulminic acid;[2] whereas the group−C≡N+O− is callednitrile oxide.
This chemical was known since the early 1800s through its salts and via the products of reactions in which it was proposed to exist,[3] but the acid itself was not detected until 1966.[1]
Fulminic acid was long believed to have a structure of H–O–N+≡C−. It wasn't until the 1966 isolation and analysis of a pure sample of fulminic acid that this structural idea was conclusively disproven.[3] The chemical that actually has that structure, isofulminic acid (atautomer of the actual fulminic acid structure) was eventually detected in 1988.[3]
The structure of the molecule has been determined bymicrowave spectroscopy with the following bond-lengths - C-H: 1.027(1)Å, C-N: 1.161(15)Å, N-O: 1.207(15)Å.[4]
A convenient synthesis involvesflash pyrolysis of certainoximes. In contrast to earlier syntheses, this method avoids the use of highly explosive metal fulminates.[5]
