Sodium phenoxide: Difference between revisions

Sodium phenoxide
Names
	Preferred IUPAC name Sodium phenoxide
	Other names Sodium phenolate
Identifiers
CAS Number	139-02-6 ;
3D model (JSmol)	Interactive image;
ChemSpider	8420;
ECHA InfoCard	100.004.862
PubChem CID	4445035;
UNII	4NC0T56V35 ;
CompTox Dashboard (EPA)	DTXSID4027072 ;
	InChI InChI=1S/C6H6O.Na/c7-6-4-2-1-3-5-6;/h1-5,7H;/q;+1/p-1 Key: NESLWCLHZZISNB-UHFFFAOYSA-M; InChI=1/C6H6O.Na/c7-6-4-2-1-3-5-6;/h1-5,7H;/q;+1/p-1 Key: NESLWCLHZZISNB-REWHXWOFAP;
	SMILES [Na+].[O-]c1ccccc1;
Properties
Chemical formula	C6H5NaO
Molar mass	116.09 g/mol
Appearance	White solid
Hazards
	Occupational safety and health (OHS/OSH):
Main hazards	Harmful, Corrosive
Flash point	Non-flammable
Autoignition; temperature	Non-flammable
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Browse history interactively

← Previous edit

Content deleted Content added

VisualWikitext

Inline

Latest revision as of 05:06, 8 July 2024

Sodium phenoxide (sodium phenolate) is an organic compound with the formula NaOC₆H₅. It is a white crystalline solid. Its anion, phenoxide, also known as phenolate, is the conjugate base of phenol. It is used as a precursor to many other organic compounds, such as aryl ethers.

Synthesis and structure

Most commonly, solutions of sodium phenoxide are produced by treating phenol with sodium hydroxide.^[2] Anhydrous derivatives can be prepared by combining phenol and sodium. A related, updated procedure uses sodium methoxide instead of sodium hydroxide:^[3]

NaOCH₃ + HOC₆H₅ → NaOC₆H₅ + HOCH₃

Sodium phenoxide can also be produced by the "alkaline fusion" of benzenesulfonic acid, whereby the sulfonate groups are displaced by hydroxide:

C₆H₅SO₃Na + 2 NaOH → C₆H₅OH + Na₂SO₃

This route once was the principal industrial route to phenol.^{[citation needed]}

Structure

Like other sodium alkoxides, solid sodium phenoxide adopts a complex structure involving multiple Na-O bonds. Solvent-free material is polymeric, each Na center being bound to three oxygen ligands as well as the phenyl ring. Adducts of sodium phenoxide are molecular, such as the cubane-type cluster [NaOPh]₄(HMPA)₄.^[4]

Subunit of the crystal structure of pure sodium phenoxide, illustrating the binding of phenoxide ions to sodium through both the oxygen and the arene.

Reactions

Sodium phenoxide is a moderately strong base. Acidification gives phenol:^[5]

PhOH ⇌ PhO⁻ + H⁺ (K = 10⁻¹⁰)

The acid-base behavior is complicated by homoassociation, reflecting the association of phenol and phenoxide.^[6]

Sodium phenoxide reacts with alkylating agents to afford alkyl phenyl ethers:^[2]

NaOC₆H₅ + RBr → ROC₆H₅ + NaBr

The conversion is an extension of the Williamson ether synthesis. With acylating agents, one obtains phenyl esters:^{[citation needed]}

NaOC₆H₅ + RC(O)Cl → RCO₂C₆H₅ + NaCl

Sodium phenoxide is susceptible to certain types of electrophilic aromatic substitutions. For example, it reacts with carbon dioxide to form 2-hydroxybenzoate, the conjugate base of salicylic acid. In general however, electrophiles irreversibly attack the oxygen center in phenoxide.^{[citation needed]}

References

^ International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. The Royal Society of Chemistry. pp. 1071, 1129. doi:10.1039/9781849733069. ISBN 978-0-85404-182-4.
^ ^a ^b C. S. Marvel; A. L. Tanenbaum (1929). "γ-Phenoxypropyl Bromide". Org. Synth. 9: 72. doi:10.15227/orgsyn.009.0072.
^ Kornblum, Nathan; Lurie, Arnold P. (1959). "Heterogeneity as a Factor in the Alkylation of Ambident Anions: Phenoxide Ions1,2". Journal of the American Chemical Society. 81 (11): 2705–2715. doi:10.1021/ja01520a030.
^ Michael Kunert, Eckhard Dinjus, Maria Nauck, Joachim Sieler "Structure and Reactivity of Sodium Phenoxide - Following the Course of the Kolbe-Schmitt Reaction" Chemische Berichte 1997 Volume 130, Issue 10, pages 1461–1465. doi:10.1002/cber.19971301017
^ Smith, Michael B.; March, Jerry (2007), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (6th ed.), New York: Wiley-Interscience, ISBN 978-0-471-72091-1
^ K. Izutsu (1990). Acid-Base Dissociation Constants in Dipolar Aprotic Solvents. Vol. 35. Blackwell Scientific Publications.

External links

Media related to Sodium phenoxide at Wikimedia Commons

[1] International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. The Royal Society of Chemistry. pp. 1071, 1129. doi:10.1039/9781849733069. ISBN 978-0-85404-182-4.

[Speed-2] C. S. Marvel; A. L. Tanenbaum (1929). "γ-Phenoxypropyl Bromide". Org. Synth. 9: 72. doi:10.15227/orgsyn.009.0072.

[3] Kornblum, Nathan; Lurie, Arnold P. (1959). "Heterogeneity as a Factor in the Alkylation of Ambident Anions: Phenoxide Ions1,2". Journal of the American Chemical Society. 81 (11): 2705–2715. doi:10.1021/ja01520a030.

[4] Michael Kunert, Eckhard Dinjus, Maria Nauck, Joachim Sieler "Structure and Reactivity of Sodium Phenoxide - Following the Course of the Kolbe-Schmitt Reaction" Chemische Berichte 1997 Volume 130, Issue 10, pages 1461–1465. doi:10.1002/cber.19971301017

[5] Smith, Michael B.; March, Jerry (2007), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (6th ed.), New York: Wiley-Interscience, ISBN 978-0-471-72091-1

[6] K. Izutsu (1990). Acid-Base Dissociation Constants in Dipolar Aprotic Solvents. Vol. 35. Blackwell Scientific Publications.

[1]

[2]

[3]

[4]

[5]

[6]

@@ Line 1: / Line 1: @@
+{{Short description|Chemical Compound}}
 {{Chembox
 | ImageFile = Structural formula of sodium phenoxide.svg
 | ImageSize = 130px
 | ImageAlt =
+| ImageFile1 = File:Sodium-phenoxide-3D-balls.png
-| IUPACName =
+| ImageAlt1 =
+| PIN = Sodium phenoxide<ref>{{cite book |author=[[International Union of Pure and Applied Chemistry]] |date=2014 |title=Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 |publisher=[[Royal Society of Chemistry|The Royal Society of Chemistry]] |pages=1071, 1129 |doi=10.1039/9781849733069 |isbn=978-0-85404-182-4}}</ref>
 | OtherNames = Sodium phenolate
 |Section1={{Chembox Identifiers
 | CASNo = 139-02-6
+| CASNo_Ref = {{cascite|correct|CAS}}
+| UNII = 4NC0T56V35
+| UNII_Ref = {{fdacite|correct|FDA}}
 |  PubChem = 4445035
 |  ChemSpiderID = 8420
-|  SMILES = c1ccc(cc1)[O-].[Na+]
+|  SMILES = [Na+].[O-]c1ccccc1
 |  InChI = 1/C6H6O.Na/c7-6-4-2-1-3-5-6;/h1-5,7H;/q;+1/p-1
 |  InChIKey = NESLWCLHZZISNB-REWHXWOFAP
@@ Line 25: / Line 31: @@
 |Section3={{Chembox Hazards
 | MainHazards = Harmful, Corrosive
-| FlashPt = Nonflammable
+| FlashPt = Non-flammable
-| AutoignitionPt = Nonflammable }}
+| AutoignitionPt = Non-flammable }}
 }}
-'''Sodium phenoxide''' ('''sodium phenolate''') is an [[organic compound]] with the formula NaOC<sub>6</sub>H<sub>5</sub>.  It is a white crystalline solid. Its anion, phenoxide, also known as phenolate, is the [[conjugate base]] of [[phenol]].  It is used as a precursor to many other organic compounds, such as aryl [[ether]]s.
+'''Sodium phenoxide''' ('''sodium phenolate''') is an [[organic compound]] with the formula NaOC<sub>6</sub>H<sub>5</sub>.  It is a white crystalline solid. Its anion, phenoxide, also known as phenolate, is the [[conjugate base]] of [[phenol]]. It is used as a precursor to many other organic compounds, such as aryl [[ether]]s.
 ==Synthesis and structure==
-Most commonly, solutions of sodium phenoxide are produced by treating phenol with sodium hydroxide.<ref name=Speed>{{cite journal|authors=C. S. Marvel, A. L. Tanenbaum|title=γ-Phenoxypropyl Bromide|journal=Org. Synth.|year=1929|volume= 9|pages=72|doi=10.15227/orgsyn.009.0072}}</ref>  Anhydrous derivatives can be prepared by combining phenol and sodium:
+Most commonly, solutions of sodium phenoxide are produced by treating phenol with sodium hydroxide.<ref name=Speed>{{cite journal|author=C. S. Marvel |author2=A. L. Tanenbaum |title=γ-Phenoxypropyl Bromide|journal=Org. Synth.|year=1929|volume= 9|page=72|doi=10.15227/orgsyn.009.0072}}</ref>  Anhydrous derivatives can be prepared by combining phenol and sodium. A related, updated procedure uses sodium methoxide instead of sodium hydroxide:<ref>{{cite journal |doi=10.1021/ja01520a030|title=Heterogeneity as a Factor in the Alkylation of Ambident Anions: Phenoxide Ions1,2|year=1959|last1=Kornblum|first1=Nathan|last2=Lurie|first2=Arnold P.|journal=Journal of the American Chemical Society|volume=81|issue=11|pages=2705–2715}}</ref>
-:Na +  HOC<sub>6</sub>H<sub>5</sub>   →   NaOC<sub>6</sub>H<sub>5</sub>  +  1/2 H<sub>2</sub>
+:NaOCH<sub>3</sub> +  HOC<sub>6</sub>H<sub>5</sub>   →   NaOC<sub>6</sub>H<sub>5</sub>  +  HOCH<sub>3</sub>
+Sodium phenoxide can also be produced by the "alkaline fusion" of [[benzenesulfonic acid]], whereby the sulfonate groups are displaced by hydroxide:
+:C<sub>6</sub>H<sub>5</sub>SO<sub>3</sub>Na  + 2 NaOH  →  C<sub>6</sub>H<sub>5</sub>OH  +  Na<sub>2</sub>SO<sub>3</sub>
+This route once was the principal industrial route to phenol.{{Citation needed|date=September 2022}}
+==Structure==
+Like other sodium [[alkoxide]]s, solid sodium phenoxide adopts a complex structure involving multiple Na-O bonds.  Solvent-free material is polymeric, each Na center being bound to three oxygen ligands [[hapticity|as well as the phenyl ring]]. Adducts of sodium phenoxide are molecular, such as the [[cubane-type cluster]] [NaOPh]<sub>4</sub>([[HMPA]])<sub>4</sub>.<ref>Michael Kunert, Eckhard Dinjus, Maria Nauck, Joachim Sieler "Structure and Reactivity of Sodium Phenoxide - Following the Course of the Kolbe-Schmitt Reaction" Chemische Berichte 1997 Volume 130, Issue 10, pages 1461–1465. {{doi|10.1002/cber.19971301017}}</ref>
+{|style="margin: 0 auto;"
-Like other sodium [[alkoxide]]s, crystalline sodium phenolate adopts a complex structure involving multiple Na-O bonds.  Solvent-free material is polymeric, each Na center being bound to three oxygen ligands as well as the [[phenyl ring]].  Adducts of sodium phenoxide are molecular, such as the [[cubane-type cluster]] [NaOPh]<sub>4</sub>([[HMPA]])<sub>4</sub>.<ref>Michael Kunert, Eckhard Dinjus, Maria Nauck, Joachim Sieler "Structure and Reactivity of Sodium Phenoxide - Following the Course of the Kolbe-Schmitt Reaction" Chemische Berichte 1997 Volume 130, Issue 10, pages 1461–1465. {{DOI|10.1002/cber.19971301017}}</ref>
+| [[File:Sodium-phenoxide-xtal-3D-SF-B.png|300px|thumb|Part of the crystal structure of pure sodium phenoxide]]
+| [[File:Sodium-phenoxide-Na-coordination-3D-balls.png|300px|thumb|Subunit of the crystal structure of pure sodium phenoxide, illustrating the binding of phenoxide ions to sodium through both the oxygen and the arene.]]
-Sodium phenoxide can be produced by the "alkaline fusion" of [[benzenesulfonic acid]], whereby the sulfonate groups are displaced by hydroxide:
+|}
-:C<sub>6</sub>H<sub>5</sub>SO<sub>3</sub>Na  + 2 NaOH  →  C<sub>6</sub>H<sub>5</sub>ONa  +  Na<sub>2</sub>SO<sub>3</sub>
-This route once was the principal industrial route to phenol.
-[[File:Sodium-phenoxide-Na-coordination-3D-balls.png|200px|right|thumb|Subunit of the structure of solvent-free sodium phenoxide, illustrating the binding of phenoxide to sodium through both the arene and the oxygen.]]
 ==Reactions==
 Sodium phenoxide is a moderately strong base.  Acidification gives phenol:<ref>{{March6th}}</ref>
 :PhOH  ⇌  PhO<sup>−</sup>  +  H<sup>+</sup>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(K = 10<sup>−10</sup>)
+The acid-base behavior is complicated by [[homoassociation]], reflecting the association of phenol and phenoxide.<ref>{{cite book|title=Acid-Base Dissociation Constants in Dipolar Aprotic Solvents|author=K. Izutsu |publisher=Blackwell Scientific Publications|year=1990|volume=35}}</ref>
-Alkylation affords phenyl ethers:<ref name=Speed/>
+Sodium phenoxide reacts with alkylating agents to afford alkyl phenyl ethers:<ref name=Speed/>
 :NaOC<sub>6</sub>H<sub>5</sub>  +  RBr →   ROC<sub>6</sub>H<sub>5</sub>  +  NaBr
-The conversion is an extension of the [[Williamson ether synthesis]].  With acylating agents, one obtains esters:
+The conversion is an extension of the [[Williamson ether synthesis]].  With acylating agents, one obtains phenyl esters:{{citation needed|date=May 2024}}
 :NaOC<sub>6</sub>H<sub>5</sub>  +  RC(O)Cl →   RCO<sub>2</sub>C<sub>6</sub>H<sub>5</sub>  +  NaCl
-Sodium phenoxide is susceptible to certain types of [[electrophilic aromatic substitution]]s. For example, it reacts with carbon dioxide to form 2-hydroxybenzoate, the conjugate base of [[salicylic acid]].  In general however, electrophiles irreversibly attack the oxygen center in phenoxide.
+Sodium phenoxide is susceptible to certain types of [[electrophilic aromatic substitution]]s. For example, it reacts with carbon dioxide to form 2-hydroxybenzoate, the conjugate base of [[salicylic acid]].  In general however, electrophiles irreversibly attack the oxygen center in phenoxide.{{citation needed|date=May 2024}}
-[[image:Kolbe-Schmitt.png|500px|center|The [[Kolbe–Schmitt reaction]].]]
+:[[image:Kolbe-Schmitt.png|500px|left|The [[Kolbe–Schmitt reaction]].]]{{clear-left}}
 ==References==