Nitrosylsulfuric acid: Difference between revisions

{{Chembox

|Watchedfields = changed

|verifiedrevid = 434912557

|Name = Nitrosylsulfuric acid

|ImageFile = Nitrosylsulfuric acid structure.svg

|ImageAlt = Structural formula of nitrosylsulfuric acid

|ImageFile1 = Nitrosylsulfuric acid molecule ball.png

|ImageSize1 = 190px

|ImageAlt1 = Ball-and-stick model of the nitrosylsulfuric acid molecule

|IUPACName = Nitrosylsulfuric acid

|OtherNames = nitrosonium bisulfate, chamber crystals

|Section1={{Chembox Identifiers

|SMILES = O=NOS(=O)(=O)O

|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

|ChemSpiderID = 74147

|PubChem = 82157

|InChI = 1/HNO5S/c2-1-6-7(3,4)5/h(H,3,4,5)

|InChIKey = VQTGUFBGYOIUFS-UHFFFAOYAM

|StdInChI_Ref = {{stdinchicite|correct|chemspider}}

|StdInChI = 1S/HNO5S/c2-1-6-7(3,4)5/h(H,3,4,5)

|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

|StdInChIKey = VQTGUFBGYOIUFS-UHFFFAOYSA-N

|CASNo_Ref = {{cascite|correct|??}}

|CASNo = 7782-78-7

|UNII_Ref = {{fdacite|correct|FDA}}

|UNII = 40K942UPM8

}}

|Section2={{Chembox Properties

|Formula = {{chem2|HSO4NO}}

|MolarMass = 127.08 g/mol

|Appearance = Pale yellow crystals<ref name=EROS>{{cite book |chapter= Nitrosylsulfuric Acid |author= George A. Olah, G. K. Surya Prakash, Qi Wang, Xing-Ya Li |title= Encyclopedia of Reagents for Organic Synthesis |doi= 10.1002/047084289X.rn060 |journal= E-EROS Encyclopedia of Reagents for Organic Synthesis |year= 2001 |isbn= 978-0471936237}}</ref>

|Density = 1.865 g/mL in<br/> 40% sulfuric acid soln <ref>{{cite web |url=https://www.sigmaaldrich.com/AT/de/product/aldrich/517070 | title=Nitrosylsulfuric acid solution | publisher=Merck}}</ref>

|Solubility = Decomposes

|SolubleOther = Soluble in [[sulfuric acid|H₂SO₄]]<ref name=EROS/>

|MeltingPtC = 70

|MeltingPt_ref = <ref name=EROS/>

|BoilingPt = Decomposes

}}

|Section7={{Chembox Hazards

|MainHazards = Oxidizer

}}

|Section8={{Chembox Related

|OtherAnions = [[Nitrosyl chloride|NOCl]]

|OtherCations = [[Sodium bisulfate|NaHSO₄]]

|OtherCompounds = [[Nitrosyl tetrafluoroborate|NOBF₄]]

}}

'''Nitrosylsulfuric acid''' is the [[chemical compound]] with the formula {{chem2|HSO4NO}}. It is a colourless solid that is used industrially in the production of [[caprolactam]],<ref name=Ullmann>{{cite encyclopedia |author1=Ritz, J. |author2=Fuchs, H. |author3=Kieczka, H. |author4=Moran, W. C. |encyclopedia= Ullmann's Encyclopedia of Industrial Chemistry |publisher= Wiley-VCH |location= Weinheim |year= 2002 |doi= 10.1002/14356007.a05_031 |chapter=Caprolactam |isbn=978-3527306732}}</ref> and was formerly part of the [[lead chamber process]] for producing [[sulfuric acid]]. The compound is the mixed [[inorganic anhydride|anhydride]] of sulfuric acid and [[nitrous acid]].

In organic chemistry, it is used as a reagent for [[nitrosylation|nitrosating]], as a [[diazotization|diazotizing agent]], and as an [[oxidizing agent]].<ref name=EROS/>

==Synthesis and reactions==

A typical procedure entails dissolving [[sodium nitrite]] in cold sulfuric acid:<ref>{{OrgSynth |author1=Hodgson, H. H.|author2=Mahadevan, A. P.|author3=Ward, E. R. |title= 1,4-Dinitronaphthalene |collvol= 3 |collvolpages= 341 |prep= cv3p0341 |year= 1955}} (diazodization followed by treatment with nitrite)</ref><ref>{{OrgSynth |author1=Sandin, R. B.|author2=Cairns, T. L. |title= 1,2,3-Triiodo-5-nitrobenzene |collvol= 2 |collvolpages= 604 |year= 1943 |prep= cv2p0604}} (diazodization followed by treatment with iodide)</ref>

:{{chem2 | HNO2 + H2SO4 -> HSO4NO + H2O }}

It can also be prepared by the reaction of [[nitric acid]] and [[sulfur dioxide]].<ref>{{Cite book |author1=Coleman, G. H. |author2=Lillis, G. A. |author3=Goheen, G. E. |title= Nitrosyl Chloride |year= 1939 |volume= 1 |pages= 55–59 |doi= 10.1002/9780470132326.ch20 |series=Inorganic Syntheses |isbn=9780470132326}} This procedure generates the nitrosylsulfuric acid as an intermediate en route to NOCl.</ref>

{{chem2|HSO4NO}} is used in [[organic chemistry]] to prepare [[diazonium salt]]s from [[amine]]s, for example in the [[Sandmeyer reaction]]. Related NO-delivery reagents include [[nitrosonium tetrafluoroborate]] {{chem2|[NO]+[BF4]-}} and [[nitrosyl chloride]].

In industry, the nitrosodecarboxylation reaction between nitrosylsulfuric acid and [[cyclohexanecarboxylic acid]] is used to generate caprolactam:<ref name=Ullmann/>

:[[File:Nitrosodecarboxylation_Caprolactam_Synthesis.svg|500px]]

==Safety==

Nitrosylsulfuric acid is a hazardous material and precautions are indicated.<ref name=EROS/>

{{Reflist}}

[[Category:Acid anhydrides]]

[[Category:Hydrogen compounds]]

[[Category:Sulfate esters]]

[[Category:Nitrogen(III) compounds]]