Nitrosyl chloride

Nitrosyl chloride
Skeletal formula of nitrosyl chloride with measurements
Spacefill model of nitrosyl chloride
Names
IUPAC name
Nitrosyl chloride[citation needed]
Identifiers
CAS Number
  • 2696-92-6 checkY
3D model (JSmol)
  • Interactive image
ChemSpider
  • 16641 checkY
ECHA InfoCard 100.018.430 Edit this at Wikidata
EC Number
  • 220-273-1
E number E919 (glazing agents, ...)
MeSH nitrosyl+chloride
PubChem CID
  • 17601
RTECS number
  • QZ7883000
UNII
  • NHE5I1E5H6 checkY
UN number 1069
CompTox Dashboard (EPA)
  • DTXSID5051945 Edit this at Wikidata
InChI
  • InChI=1S/ClNO/c1-2-3 checkY
    Key: VPCDQGACGWYTMC-UHFFFAOYSA-N checkY
  • ClN=O
Properties
Chemical formula
 NOCl
Molar mass 65.459 g mol−1
Appearance yellow gas
Density 2.872 mg mL−1
Melting point −59.4 °C (−74.9 °F; 213.8 K)
Boiling point −5.55 °C (22.01 °F; 267.60 K)
Solubility in water
 Reacts
Structure
Molecular shape
 Dihedral, digonal
Hybridisation sp2 at N
1.90 D
Thermochemistry
Std molar
entropy (S⦵298)
 261.68 J K−1 mol−1
Std enthalpy of
formation (ΔfH⦵298)
 51.71 kJ mol−1
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g. calciumSpecial hazard W+OX: Reacts with water in an unusual or dangerous manner AND is oxidizer
3
0
1
W
OX
Safety data sheet (SDS) inchem.org
Related compounds
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references
Chemical compound

Nitrosyl chloride is the chemical compound with the formula NOCl. It is a yellow gas that is commonly encountered as a component of aqua regia, a mixture of 3 parts concentrated hydrochloric acid and 1 part of concentrated nitric acid. It is a strong electrophile and oxidizing agent. It is sometimes called Tilden's reagent, after William A. Tilden, who was the first to produce it as a pure compound.[1]

Structure and synthesis

The molecule is bent. A double bond exists between N and O (distance = 1.16 Å) and a single bond between N and Cl (distance = 1.96 Å). The O=N–Cl angle is 113°.[2]

Production

Nitrosyl chloride can be produced in many ways.

HCl + NOHSO4 → H2SO4 + NOCl
  • A more convenient laboratory method involves the (reversible) dehydration of nitrous acid by HCl[4]
HNO2 + HCl → H2O + NOCl
Cl2 + 2 NO → 2 NOCl
  • By reduction of nitrogen dioxide with hydrogen chloride:[5]
2NO2 + 4 HCl → 2NOCl + 2H2O + Cl2

Occurrence in aqua regia

NOCl also arises from the combination of hydrochloric and nitric acids according to the following reaction:[6]

HNO3 + 3 HCl → 2[Cl] + 2 H2O + NOCl

In nitric acid, NOCl is readily oxidized into nitrogen dioxide. The presence of NOCl in aqua regia was described by Edmund Davy in 1831.[7]

Reactions

NOCl behaves as an electrophile and an oxidant in most of its reactions. With halide acceptors, for example antimony pentachloride, converts to nitrosonium salts:

NOCl + SbCl5 → [NO]+[SbCl6]−

In a related reaction, sulfuric acid gives nitrosylsulfuric acid, the mixed acid anhydride of nitrous and sulfuric acid:

ClNO + H2SO4 → ONHSO4 + HCl

NOCl reacts with silver thiocyanate to give silver chloride and the pseudohalogen nitrosyl thiocyanate:

ClNO + AgSCN → AgCl + ONSCN

Similarly, it reacts with silver cyanide to give nitrosyl cyanide.[8]

Nitrosyl chloride is used to prepare metal nitrosyl complexes. With molybdenum hexacarbonyl, NOCl gives the dinitrosyldichloride complex:[9]

Mo(CO)6 + 2 NOCl → MoCl2(NO)2 + 6 CO

It dissolves platinum:[10]

Pt + 6 NOCl → (NO+)2[PtCl6]2- + 4 NO

Applications in organic synthesis

Aside from its role in the production of caprolactam, NOCl finds some other uses in organic synthesis. It adds to alkenes to afford α-chloro oximes.[11] The addition of NOCl follows the Markovnikov rule. Ketenes also add NOCl, giving nitrosyl derivatives:

H2C=C=O + NOCl → ONCH2C(O)Cl

Epoxides react with NOCl to give an α-chloronitritoalkyl derivatives. In the case of propylene oxide, the addition proceeds with high regiochemistry:[12]

It converts amides to N-nitroso derivatives.[13] NOCl converts some cyclic amines to the alkenes. For example, aziridine reacts with NOCl to give ethene, nitrous oxide and hydrogen chloride.

Industrial applications

NOCl and cyclohexane react photochemically to give cyclohexanone oxime hydrochloride. This process exploits the tendency of NOCl to undergo photodissociation into NO and Cl radicals. The cyclohexanone oxime is converted to caprolactam, a precursor to nylon-6.[3]

Safety

Nitrosyl chloride is very toxic and irritating to the lungs, eyes, and skin.

References

  1. ^ Tilden, William A. (1874). "XXXII.—On aqua regia and the nitrosyl chlorides". J. Chem. Soc. 27: 630–636. doi:10.1039/JS8742700630.
  2. ^ Holleman, A. F.; Wiberg, E. (2001). Inorganic Chemistry. San Diego: Academic Press. ISBN 0-12-352651-5.
  3. ^ a b Ritz, Josef; Fuchs, Hugo; Kieczka, Heinz; Moran, William C. Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a05_031. ISBN 978-3527306732.
  4. ^ Morton, J. R.; Wilcox, H. W.; Moellerf, Therald; Edwards, Delwin C. (1953). "Nitrosyl Chloride". In Bailar, John C. Jr (ed.). Inorganic Syntheses. Vol. 4. McGraw‐Hill. p. 48. doi:10.1002/9780470132357.ch16. ISBN 9780470132357.
  5. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 456. ISBN 978-0-08-037941-8.
  6. ^ Beckham, L. J.; Fessler, W. A.; Kise, M. A. (1951). "Nitrosyl Chloride". Chemical Reviews. 48 (3): 319–396. doi:10.1021/cr60151a001. PMID 24541207.
  7. ^ Edmund Davy (1830–1837). "On a New Combination of Chlorine and Nitrous Gas". Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London. 3: 27–29. JSTOR 110250.
  8. ^ Kirby, G. W. (1977). "Tilden Lecture. Electrophilic C-Nitroso Compounds". Chemical Society Reviews. 6: 1. doi:10.1039/CS9770600001.
  9. ^ Johnson, B. F. G.; Al-Obadi, K. H. (1970). "Dihalogenodinitrosylmolybdenum and Dihalogenodinitrosyltungsten". Inorganic Syntheses. Vol. 12. pp. 264–266. doi:10.1002/9780470132432.ch47. ISBN 9780470132432. {{cite book}}: |journal= ignored (help)
  10. ^ Moravek, Richard T. (1986). "Nitrosyl Hexachloroplatinate(IV)". Inorganic Syntheses. Vol. 24. pp. 217–220. doi:10.1002/9780470132555.ch63. ISBN 9780470132555.
  11. ^ Ohno, M.; Naruse, N.; Terasawa, I. (1969). "7-Cyanoheptanal". Org. Synth. 49: 27. doi:10.15227/orgsyn.049.0027.
  12. ^ Malinovskii, M. S.; Medyantseva, N. M. (1953). "Olefin Oxides. IX. Condensation of Olefin Oxides with Nitrosyl Chloride". Zhurnal Obshchei Khimii. 23: 84–6. (translated from Russian)
  13. ^ Van Leusen, A. M.; Strating, J. (1977). "p-Tolylsulfonyldiazomethane". Org. Synth. 57: 95. doi:10.15227/orgsyn.057.0095.

External links

  • Media related to Nitrosyl chloride at Wikimedia Commons
  • v
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Salts and covalent derivatives of the chloride ion
HCl He
LiCl BeCl2 B4Cl4
B12Cl12
BCl3
B2Cl4
+BO3 		C2Cl2
C2Cl4
C2Cl6
CCl4
+C
+CO3 		NCl3
ClN3
+N
+NO3 		ClxOy
Cl2O
Cl2O2
ClO
ClO2
Cl2O4
Cl2O6
Cl2O7
ClO4
+O 		ClF
ClF3
ClF5 		Ne
NaCl MgCl2 AlCl
AlCl3 		Si5Cl12
Si2Cl6
SiCl4 		P2Cl4
PCl3
PCl5
+P 		S2Cl2
SCl2
SCl4
+SO4 		Cl2 Ar
KCl CaCl
CaCl2 		ScCl3 TiCl2
TiCl3
TiCl4 		VCl2
VCl3
VCl4
VCl5 		CrCl2
CrCl3
CrCl4 		MnCl2
MnCl3 		FeCl2
FeCl3 		CoCl2
CoCl3 		NiCl2 CuCl
CuCl2 		ZnCl2 GaCl
GaCl3 		GeCl2
GeCl4 		AsCl3
AsCl5
+As 		Se2Cl2
SeCl2
SeCl4 		BrCl Kr
RbCl SrCl2 YCl3 ZrCl3
ZrCl4 		NbCl3
NbCl4
NbCl5 		MoCl2
MoCl3
MoCl4
MoCl5
MoCl6 		TcCl3
TcCl4 		RuCl2
RuCl3
RuCl4 		RhCl3 PdCl2 AgCl CdCl2 InCl
InCl2
InCl3 		SnCl2
SnCl4 		SbCl3
SbCl5 		Te3Cl2
TeCl2
TeCl4 		ICl
ICl3 		XeCl
XeCl2
XeCl4
CsCl BaCl2 * LuCl3 HfCl4 TaCl3
TaCl4
TaCl5 		WCl2
WCl3
WCl4
WCl5
WCl6 		ReCl3
ReCl4
ReCl5
ReCl6 		OsCl2
OsCl3
OsCl4
OsCl5 		IrCl2
IrCl3
IrCl4 		PtCl2
PtCl4 		AuCl
(Au[AuCl4])2
AuCl3 		Hg2Cl2
HgCl2 		TlCl
TlCl3 		PbCl2
PbCl4 		BiCl3 PoCl2
PoCl4 		AtCl Rn
FrCl RaCl2 ** LrCl3 RfCl4 DbCl5 SgO2Cl2 BhO3Cl Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
 
* LaCl3 CeCl3 PrCl3 NdCl2
NdCl3 		PmCl3 SmCl2
SmCl3 		EuCl2
EuCl3 		GdCl3 TbCl3 DyCl2
DyCl3 		HoCl3 ErCl3 TmCl2
TmCl3 		YbCl2
YbCl3
** AcCl3 ThCl3
ThCl4 		PaCl4
PaCl5 		UCl3
UCl4
UCl5
UCl6 		NpCl3 PuCl3 AmCl2
AmCl3 		CmCl3 BkCl3 CfCl3
CfCl2 		EsCl2
EsCl3 		FmCl2 MdCl2 NoCl2