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{{short description|Chemical compound}}
{{Chembox
| Watchedfields = changed
| verifiedrevid = 464400313
| Name =
| ImageFile = Sodium borohydride.svg
| ImageSize =
| ImageName = Wireframe model of sodium borohydride
| ImageFile1 = sodium borohydride.jpg
| ImageFileL1 = Sodium-3D.png
| ImageFileR1 = Borohydride-3D-vdW.png
| ImageSize1 =
| OtherNames =
| IUPACName = Sodium tetrahydridoborate(1–)
| SystematicName = Sodium boranuide
| Section1 = {{Chembox Identifiers
| InChI = 1S/BH4.Na/h1H4;/q-1;+1
| InChIKey1 = YOQDYZUWIQVZSF-UHFFF
| CASNo = 16940-66-2
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo1_Ref = {{cascite|correct|??}}
| CASNo1 = 15681-89-7
| CASNo1_Comment = (2''D''4)
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 87L0B9CPPA
| UNII1_Ref = {{fdacite|correct|FDA}}
| PubChem = 4311764
| PubChem1 = 23673181
| PubChem1_Comment = (2''D''4)
| PubChem2 = 23671303
| PubChem2_Comment = (3''T''4)
| ChemSpiderID = 26189
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID1_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID1 = 9052313
| ChemSpiderID1_Comment = (2''D''4)
| ChemSpiderID2_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID2 = 9312193
| ChemSpiderID2_Comment = (3''T''4)
| EINECS = 241-004-4
| UNNumber = 1426
| MeSHName = Sodium+borohydride
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 50985
| RTECS = ED3325000
| SMILES = [Na+].[BH4-]
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/BH4.Na/h1H4;/q-1;+1
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = YOQDYZUWIQVZSF-UHFFFAOYSA-N
| Gmelin = 23167}}
| Section2 = {{Chembox Properties
| Formula = NaBH4
| Appearance = white crystals [[hygroscopic]]
| MolarMass = 37.83 g/mol
| MeltingPtC = 400
| BoilingPtC =
| MeltingPt_ref = (decomposes)<ref name=crc/>
| Density = 1.07 g/cm3<ref name=crc>{{cite book | editor= Haynes, William M. | year = 2011 | title = CRC Handbook of Chemistry and Physics | edition = 92nd | publisher = [[CRC Press]] | isbn = 978-1439855119|page= 4.89| title-link = CRC Handbook of Chemistry and Physics }}</ref>
| Solubility = 550 g/L<ref name=crc/>
| SolubleOther = soluble in liquid [[ammonia]], [[amine]]s, [[pyridine]]
}}
| Section3 = {{Chembox Structure
| Structure_ref =<ref>{{cite journal|doi=10.1107/S0365110X54002034|title=The unit cell of potassium borohydride, KBH4, at 90° K|journal=Acta Crystallogr|year=1954|volume=7|issue=8|author=Ford, P. T. and Powell, H. M. |pages= 604–605|doi-access=free}}</ref>
| CrystalStruct = Cubic (NaCl), [[Pearson symbol|cF8 ]]
| SpaceGroup = Fm{{overline|3}}m, No. 225
| PointGroup =
| LattConst_a = 0.6157 nm
| LattConst_b =
| LattConst_c =
| LattConst_alpha =
| LattConst_beta =
| LattConst_gamma =
| LattConst_ref =
| LattConst_Comment =
| UnitCellVolume =
| UnitCellFormulas =
}}
| Section4 =
| Section5 =
| Section6 =
| Section7 = {{Chembox Hazards
| HPhrases = {{H-phrases|260|301|311|314}}
| PPhrases = {{P-phrases|223|231|232|280|301+310|370+378|422}}
| NFPA-H = 3 | NFPA-F = 1 | NFPA-R = 2 | NFPA-S = W
| FlashPtC = 70
| AutoignitionPt = ca.
| AutoignitionPtC = 220
| ExploLimits = 3%
| LD50 = 160 mg/kg (Oral – Rat) 230 mg/kg (Dermal – Rabbit)
}}
| Section8 = {{Chembox Related
| OtherAnions = [[Sodium cyanoborohydride]] [[Sodium hydride]] [[Sodium borate]] [[Borax]] [[Sodium aluminum hydride]]
| OtherCations = [[Lithium borohydride]]
| OtherCompounds = [[Lithium aluminium hydride]] [[Sodium triacetoxyborohydride]]
}}
}}

'''Sodium borohydride''', also known as '''sodium tetrahydridoborate''' and '''sodium tetrahydroborate''',<ref name="google">{{cite book|title=Inorganic Syntheses|author=Busch, D.H.|date=2009|volume=20|publisher=Wiley|isbn=9780470132869|url=https://books.google.com/books?id=XktiIRlSBlkC|page=137|access-date=20 May 2015}}</ref> is an [[inorganic compound]] with the [[chemical formula|formula]] [[sodium|Na]][[borohydride|BH4]]. This white solid, usually encountered as a powder, is a [[reducing agent]] that finds application in chemistry, both in the laboratory and on an industrial scale. It has been tested as pretreatment for pulping of wood, but is too costly to be commercialized.<ref name=Ullmann/><ref name=kraftpulping>{{cite journal|author=Istek, A. and Gonteki, E. |title=Utilization of sodium borohydride (NaBH4) in kraft pulping process|url=http://www.jeb.co.in/journal_issues/200911_nov09/paper_05.pdf|journal=Journal of Environmental Biology|volume=30|issue=6|pages= 951–953 |year=2009|pmid=20329388}}</ref> The compound is soluble in [[Alcohol (chemistry)|alcohol]]s, certain [[ether]]s, and water, although it slowly hydrolyzes.<ref name=eEROS>{{cite encyclopedia|author1=Banfi, L. |author2=Narisano, E. |author3=Riva, R. |author4=Stiasni, N. |author5=Hiersemann, M. |encyclopedia=Encyclopedia of Reagents for Organic Synthesis|year=2004|publisher=J. Wiley & Sons |location=New York|doi=10.1002/047084289X.rs052|isbn=978-0471936237|chapter=Sodium Borohydride}}</ref>

The compound was discovered in the 1940s by [[Hermann Irving Schlesinger|H. I. Schlesinger]], who led a team seeking volatile uranium compounds.<ref>{{cite journal |author1=Schlesinger, H. I. |author2-link=Herbert C. Brown |author2=Brown, H. C. |author3=Abraham, B. |author4=Bond, A. C. |author5=Davidson, N. |author6=Finholt, A. E. |author7=Gilbreath, J. R. |author8=Hoekstra, H. |author9=Horvitz, L. |author10=Hyde, E. K. |author11=Katz, J. J. |author12=Knight, J. |author13=Lad, R. A. |author14=Mayfield, D. L. |author15=Rapp, L. |author16=Ritter, D. M. |author17=Schwartz, A. M. |author18=Sheft, I. |author19=Tuck, L. D. |author20=Walker, A. O. | title = New developments in the chemistry of diborane and the borohydrides. General summary | journal = [[J. Am. Chem. Soc.]] | year = 1953 | volume = 75 | pages = 186–90 | doi = 10.1021/ja01097a049}}</ref><ref name=sch1945>Hermann I Schlesinger and Herbert C Brown (1945) "[https://patentimages.storage.googleapis.com/99/ba/68/f4852875a53aff/US2461661.pdf Preparation of alkali metal compounds]". US Patent 2461661. Granted on 1949-02-15; expired on 1966-02-15.</ref> Results of this wartime research were declassified and published in 1953.

==Properties==
{| class="wikitable floatleft"
|-
! Solvent !! Solubility (g/100 mL)<ref name=eEROS/>
|-
| MeOH || 13
|-
| EtOH || 3.16
|-
| [[Diglyme]] || 5.15
|-
| Et2O || insoluble
|}

Sodium borohydride is an odorless white to gray-white [[microcrystalline]] powder that often forms lumps. It can be purified by recrystallization from warm (50 °C) [[diglyme]].<ref>Brown, H. C. “Organic Syntheses via Boranes” John Wiley & Sons, Inc. New York: 1975. {{ISBN|0-471-11280-1}}. page 260-1.</ref> Sodium borohydride is soluble in [[protic solvents]] such as water and lower alcohols. It also reacts with these [[protic solvent]]s to produce H2; however, these reactions are fairly slow. Complete decomposition of a methanol solution requires nearly 90 min at 20 °C.<ref>{{cite journal|last1=Lo|first1=Chih-ting F.|last2=Karan|first2=Kunal|last3=Davis|first3=Boyd R.|title=Kinetic Studies of Reaction between Sodium Borohydride and Methanol, Water, and Their Mixtures|journal=Industrial & Engineering Chemistry Research|volume=46|issue=17|pages=5478–5484|doi=10.1021/ie0608861|year=2007}}</ref> It decomposes in neutral or acidic aqueous solutions, but is stable at pH 14.<ref name=eEROS/>

===Structure===
NaBH4 is a salt, consisting of the tetrahedral [BH4]− anion. The solid is known to exist as three [[Polymorphism (materials science)|polymorphs]]: ''α'', ''β'' and ''γ''. The stable phase at room temperature and pressure is ''α''-NaBH4, which is cubic and adopts an [[Halite structure|NaCl]]-type structure, in the ''Fm{{overline|3}}m'' [[space group]]. At a pressure of 6.3 GPa, the structure changes to the tetragonal ''β''-NaBH4 (space group ''P421c'') and at 8.9 GPa, the orthorhombic ''γ''-NaBH4 (space group ''Pnma'') becomes the most stable.<ref>{{ cite journal | journal = Appl. Phys. Lett. | year = 2005 | volume = 87 | page = 261916 | doi = 10.1063/1.2158505 | title = Structural transitions in NaBH[sub 4] under pressure | issue = 26 }}</ref><ref>{{ cite journal | journal = Phys. Rev. B | year = 2007 | volume = 76 | page = 092104 | doi = 10.1103/PhysRevB.76.092104 | title = High-pressure phase of NaBH4: Crystal structure from synchrotron powder diffraction data | issue = 9 | bibcode = 2007PhRvB..76i2104F | last1 = Filinchuk | first1 = Y. | last2 = Talyzin | first2 = A. V. | last3 = Chernyshov | first3 = D. | last4 = Dmitriev | first4 = V. | s2cid = 122588719 | url = https://semanticscholar.org/paper/4209bdf1ab789738811cc406d4e0a727cdfc4d51 }}</ref><ref>{{ cite journal | journal = J. Phys. Chem. B | year = 2007 | volume = 111 | issue = 50 | pages = 13873–13876 | doi = 10.1021/jp709840w | pmid = 18031032 | title = Pressure-driven phase transitions in NaBH4: theory and experiments | last1 = Kim | first1 = E. | last2 = Kumar | first2 = R. | last3 = Weck | first3 = P. F. | last4 = Cornelius | first4 = A. L. | last5 = Nicol | first5 = M. | last6 = Vogel | first6 = S. C. | last7 = Zhang | first7 = J. | last8 = Hartl | first8 = M. | last9 = Stowe | first9 = A. C. | last10 = Daemen | first10 = L. | last11 = Zhao | first11 = Y. }}</ref>

<center>
{| style="margin:auto;" class="wikitable"
| <center>[[File:Alpha-sodium-borohydride-xtal-2007-3D-balls.png|170px]]</center>||<center>[[File:Beta-sodium-borohydride-xtal-2007-3D-balls.png|220px]]</center>||<center>[[File:Gamma-sodium-borohydride-xtal-2007-3D-balls.png|190px]]</center>
|-
| <center>''α''-NaBH4</center>||<center>''β''-NaBH4</center>||<center>''γ''-NaBH4</center>
|}
</center>

==Synthesis and handling==

For commercial NaBH4 production, the Brown-Schlesinger process and the [[Bayer process]] are the most popular methods. In the Brown-Schlesinger process sodium borohydride is industrially prepared from [[sodium hydride]] (produced by reacting Na and H2) and [[trimethyl borate]] at 250–270 °C:

:B(OCH3)3 + 4 NaH → NaBH4 + 3 NaOCH3

Millions of kilograms are produced annually, far exceeding the production levels of any other hydride reducing agent.<ref name=Ullmann>{{Ullmann|doi=10.1002/14356007.a13_199|title= Hydrides|year=2000|last1=Rittmeyer|first1=Peter|last2=Wietelmann|first2= Ulrich|isbn=3527306730}}</ref> It can also be produced from inorganic borates, including [[borosilicate glass]]<ref>Schubert, F.; Lang, K.; Burger, A. (1960) "Alkali metal borohydrides" (Bayer). German patent DE 1088930 19600915 (ChemAbs: 55:120851). Supplement to. to Ger. 1,067,005 (CA 55, 11778i). From the abstract: "Alkali metal borosilicates are treated with alkali metal hydrides in approx. 1:1 ratio at >100 °C with or without H pressure"</ref> and [[borax]] (Na2B4O7):
:Na2B4O7 + 16 Na + 8 H2 + 7 SiO2 → 4 NaBH4 + 7 Na2SiO3

Magnesium is a less expensive reductant, and could in principle be used instead:<ref name="Production 1">Wu, Ying et al. (2004) [https://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/review_chemical_processes.pdf Review of Chemical Processes for the Synthesis of Sodium Borohydride]. Millennium Cell Inc. </ref><ref name="Production 2">{{cite journal|doi=10.3390/inorganics6010010|title=A Recycling Hydrogen Supply System of NaBH4 Based on a Facile Regeneration Process: A Review|journal=Inorganics|volume=6|pages=10|year=2018|last1=Ouyang|first1=Liuzhang|last2=Zhong|first2=Hao|last3=Li|first3=Hai-Wen|last4=Zhu|first4=Min|doi-access=free}}</ref>
:8 MgH2 + Na2B4O7 + Na2CO3 → 4 NaBH4 + 8 MgO + CO2
and
:2 MgH2 + NaBO2 → NaBH4 + 2 MgO

==Reactivity==
===Organic synthesis===
NaBH4 [[carbonyl reduction|reduces many organic carbonyls]], depending on the precise conditions. Most typically, it is used in the laboratory for converting ketones and aldehydes to alcohols. It efficiently reduces [[acyl chloride]]s, [[Organic acid anhydride|anhydrides]], α-hydroxy[[Lactonase|lactones]], [[thioester]]s, and [[imine]]s at room temperature or below. It reduces esters slowly and inefficiently with excess reagent and/or elevated temperatures, while carboxylic acids and amides are not reduced at all.<ref>{{Citation|last1=Banfi|first1=Luca|title=Sodium Borohydride|date=2014|encyclopedia=Encyclopedia of Reagents for Organic Synthesis|pages=1–13|publisher=John Wiley & Sons|doi=10.1002/047084289x.rs052.pub3|isbn=9780470842898|last2=Narisano|first2=Enrica|last3=Riva|first3=Renata|last4=Stiasni|first4=Nikola|last5=Hiersemann|first5=Martin|last6=Yamada|first6=Tohru|last7=Tsubo|first7=Tatsuyuki}}</ref> NaBH4 reacts with water and alcohols, with evolution of hydrogen gas and formation of the corresponding borate, the reaction being especially fast at low pH.

Nevertheless, an alcohol, often methanol or ethanol, is generally the solvent of choice for sodium borohydride reductions of ketones and aldehydes. The mechanism of ketone and aldehyde reduction has been scrutinized by kinetic studies, and contrary to popular depictions in textbooks, the mechanism does not involve a 4-membered transition state like alkene hydroboration,<ref>{{Cite book|title=Organic chemistry|author=Carey, Francis A.|others=Giuliano, Robert M., 1954–|isbn=9780073511214|edition= Tenth |location=New York, NY|oclc=915135847|date = 2016-01-07}}</ref> or a six-membered transition state involving a molecule of the alcohol solvent.<ref>{{Cite book|title=Organic chemistry|last=Loudon|first=Marc|date=2009|publisher=Roberts and Co|isbn=9780981519432|edition=5th|location=Greenwood Village, Colo.|oclc=263409353|url-access=registration|url=https://archive.org/details/organicchemistry0000loud}}</ref> Hydrogen-bonding activation is required, as no reduction occurs in an aprotic solvent like diglyme. However, the rate order in alcohol is 1.5, while carbonyl compound and borohydride are both first order, suggesting a mechanism more complex than one involving a six-membered transition state that includes only a single alcohol molecule. It was suggested that the simultaneous activation of the carbonyl compound and borohydride occurs, via interaction with the alcohol and alkoxide ion, respectively, and that the reaction proceeds through an open transition state.<ref>{{Cite journal|last1=Wigfield|first1=Donald C.|last2=Gowland|first2=Frederick W.|date=March 1977|title=The kinetic role of hydroxylic solvent in the reduction of ketones by sodium borohydride. New proposals for mechanism, transition state geometry, and a comment on the origin of stereoselectivity|journal=The Journal of Organic Chemistry|volume=42|issue=6|pages=1108–1109|doi=10.1021/jo00426a048}}</ref><ref>{{Cite journal|last=Wigfield|first=Donald C.|date=January 1979|title=Stereochemistry and mechanism of ketone reductions by hydride reagents|journal=Tetrahedron|volume=35|issue=4|pages=449–462|doi=10.1016/0040-4020(79)80140-4|issn=0040-4020}}</ref>

α,β-Unsaturated ketones tend to be reduced by NaBH4 in a 1,4-sense, although mixtures are often formed. Addition of cerium chloride improves the [[Chemoselectivity|selectivity]] for 1,2-reduction of unsaturated ketones ([[Luche reduction]]). α,β-Unsaturated esters also undergo 1,4-reduction in the presence of NaBH4.<ref name="eEROS" />

The NaBH4-MeOH system, formed by the addition of [[methanol]] to sodium borohydride in refluxing THF, reduces esters to the corresponding alcohols.<ref name='Costa'>{{cite journal | first1 = Jorge C.S. | last1 = da Costa | first2= Karla C. | last2= Pais | first3= Elisa L. | last3 = Fernandes | first4 = Pedro S. M. | last4 = de Oliveira | first5 = Jorge S. | last5 = Mendonça | first6 =Marcus V. N. | last6 = de Souza | first7 = Mônica A. | last7 = Peralta | first8 = Thatyana R.A. | last8 = Vasconcelos | title = Simple reduction of ethyl, isopropyl and benzyl aromatic esters to alcohols using sodium borohydride-methanol system | journal = [[Arkivoc]] | year = 2006 | pages = 128–133 | url = http://www.arkat-usa.org/ark/journal/2006/I01_General/1523/05-1523A%20as%20published%20mainmanuscript.pdf | access-date = 29 August 2006 }}</ref> Mixing water or an alcohol with the borohydride converts some of it into unstable hydride ester, which is more efficient at reduction, but the reductant eventually decomposes spontaneously to produce hydrogen gas and borates. The same reaction can also occur intramolecularly: an α-ketoester converts into a diol, since the alcohol produced attacks the borohydride to produce an ester of the borohydride, which then reduces the neighboring ester.<ref>{{cite journal|title=Mechanistic rationale for the NaBH4 reduction of α-keto esters|journal=Tetrahedron Letters|volume=40|issue=28|pages=5193–5196|doi=10.1016/S0040-4039(99)01006-0|year=1999|last1=Dalla|first1=V.|last2=Catteau|first2=J.P.|last3=Pale|first3=P.}}</ref>

The reactivity of NaBH4 can be enhanced or augmented by a variety of compounds.<ref>{{cite journal|last=Periasamy|first=Mariappan|author2=Thirumalaikumar, Muniappan |title=Methods of enhancement of reactivity and selectivity of sodium borohydride for applications in organic synthesis|journal=Journal of Organometallic Chemistry|year=2000|volume=609|issue=1–2|pages=137–151|doi=10.1016/S0022-328X(00)00210-2}}</ref><ref>{{cite journal|last=Nora de Souza|first=Marcus Vinícius|author2=Alves Vasconcelos |author3=Thatyana Rocha |title=Recent methodologies mediated by sodium borohydride in the reduction of different classes of compounds|journal=Applied Organometallic Chemistry|date=1 November 2006|volume=20|issue=11|pages=798–810|doi=10.1002/aoc.1137}}</ref>

===Oxidation===
Oxidation with [[iodine]] in [[tetrahydrofuran]] gives [[borane–tetrahydrofuran]], which can reduce carboxylic acids.<ref>{{cite journal|last=Kanth|first=J. V. Bhaskar|author2=Periasamy, Mariappan |title=Selective reduction of carboxylic acids into alcohols using sodium borohydride and iodine|journal=The Journal of Organic Chemistry|date=1 September 1991|volume=56|issue=20|pages=5964–5965|doi=10.1021/jo00020a052}}</ref>

Partial oxidation of [[borohydride]] with iodine gives [[octahydrotriborate]]:<ref>{{cite book |doi=10.1002/9780470132463.ch25|series=Inorganic Syntheses|year=1974|last1=Ryschlewitsch|first1=G. E.|last2=Nainan|first2=K. C.|last5=Dewkett|first5=W. J.|last6=Grace|first6=M.|last7=Beall|first7=H.|title=Octahydrotriborate (1-) ([B3 H8 ]) salts|pages=111–118|volume=15|isbn=9780470132463}}</ref>
:3{{nbsp}}BH4− + I2 → B3H8− + 2{{nbsp}}H2 + 2{{nbsp}}I−

===Coordination chemistry===
BH4− is a [[ligand]] for metal ions. Such borohydride complexes are often prepared by the action of NaBH4 (or the LiBH4) on the corresponding metal halide. One example is the [[titanocene]] derivative:<ref>{{cite book | last1 = Lucas | first1 = C. R. | year = 1977 | title = Bis(5-Cyclopentadienyl) [Tetrahydroborato(1-)]Titanium | series = Inorganic Syntheses | volume = 17 | page = 93 | doi = 10.1002/9780470132487.ch27 | isbn = 9780470132487 }}</ref>
:2 (C5H5)2TiCl2 + 4 NaBH4 → 2 (C5H5)2TiBH4 + 4 NaCl + B2H6 + H2

===Protonolysis and hydrolysis===
In the presence of metal catalysts, sodium borohydride hydrolyzes with release of hydrogen. Exploiting this reactivity, sodium borohydride has been used in prototypes of the [[direct borohydride fuel cell]].
:NaBH4 + 2 H2O → NaBO2 + 4 H2 (ΔH < 0)

==Applications==
The principal application of sodium borohydride is the production of [[sodium dithionite]] from sulfur dioxide: Sodium dithionite is used as a bleaching agent for wood pulp and in the dyeing industry. 

Sodium borohydride [[organic reduction|reduces]] [[aldehyde]]s and [[ketone]]s to give the related [[Alcohol (chemistry)|alcohol]]s. This reaction is used in the production of various antibiotics including [[chloramphenicol]], [[dihydrostreptomycin]], and [[thiophenicol]]. Various steroids and [[vitamin A]] are prepared using sodium borohydride in at least one step.<ref name=Ullmann/>

Sodium borohydride has been considered as a solid state [[hydrogen storage]] candidate. Although practical temperatures and pressures for hydrogen storage have not been achieved, in 2012 a core–shell [[nanostructure]] of sodium borohydride was used successfully to store, release and reabsorb hydrogen under moderate conditions.<ref>Stuart Gary, "[http://www.abc.net.au/science/articles/2012/08/16/3569478.htm Hydrogen storage no longer up in the air]" in ''[[ABC News and Current Affairs|ABC Science]]'' 16 August 2012, citing {{cite journal |last1= Christian|first1= Meganne|last2= Aguey-Zinsou|first2= Kondo François|year= 2012|title= Core–Shell Strategy Leading to High Reversible Hydrogen Storage Capacity for NaBH4|journal= [[ACS Nano]]|volume= 6|issue= 9|pages= 7739–7751|doi=10.1021/nn3030018 |pmid= 22873406}}</ref>

Sodium borohydride can be used to reduce [[foxing]] in old books and documents.<ref>{{cite web|url=https://blog.bookstellyouwhy.com/bid/230209/how-to-prevent-and-reverse-foxing-in-rare-books|title=How to Prevent and Reverse Foxing in Rare Books|first=Kristin|last=Masters|website=bookstellyouwhy.com|access-date=3 April 2018}}</ref> This treatment should only be done by a skilled professional conservator/restorer as damage to paper can ensue if the reducing agent is not applied correctly, such as over bleaching and bubbling of paper.

==Safety==
Sodium borohydride is a source of [[hydrogen]] or [[diborane]], which are both flammable. Spontaneous ignition can result from solution of sodium borohydride in [[dimethylformamide]]. Bulk solutions of sodium borohydride are often prepared with excess sodium hydroxide, which is corrosive.

==See also==
Many derivatives and analogues of sodium borohydride exhibit modified reactivity of value in organic synthesis.<ref>Seyden-Penne, J. (1991) [http://rushim.ru/books/mechanizms/reductions.pdf ''Reductions by the Alumino- and Borohydrides in Organic Synthesis'']. VCH–Lavoisier: Paris. p. 9. {{ISBN|978-0-471-19036-3}}</ref>

*[[Sodium triacetoxyborohydride]], a milder reductant owing to the presence of more electron-withdrawing acetate in place of hydride.
*[[Sodium triethylborohydride]], a stronger reductant owing to the presence of electron-donating ethyl groups in place of hydride.
*[[sodium cyanoborohydride]], a milder reductant owing to the presence of more electron-withdrawing cyanide in place of hydride. Useful for reductive aminations.

*[[Lithium borohydride]], a more strongly reducing reagent.
*[[L-selectride]] (lithium tri-''sec''-butylborohydride), a more strongly reducing are derivative.

*[[Lithium aluminium hydride]], a more strongly reducing reagent, capable of reducing esters and amides.

==References==
{{Reflist}}

==External links==
*[https://web.archive.org/web/20060209040519/http://www.npi.gov.au/database/substance-info/profiles/15.html National Pollutant Inventory – Boron and compounds]
*[https://archive.today/20130202223031/http://www.sodiumborohydride.com/wcm/products/product_detail.page?display-mode=msds&product=1120465&application=1120785 MSDS for Sodium Borohydride]
*[https://web.archive.org/web/20050305180812/http://merit.hydrogen.co.jp/ Materials & Energy Research Institute Tokyo, Ltd.]
*[https://web.archive.org/web/20051201011849/http://www.sodiumborohydride.com/technical.html Chemo- and stereoselectivity using Borohydride reagents]
*[http://www.sciencelab.com/msds.php?msdsId=9924969 Material Safety Data Sheet]

{{Sodium compounds}}

{{Authority control}}

[[Category:Sodium compounds]]
[[Category:Borohydrides]]
[[Category:Reducing agents]]

Sodium borohydride - Revision history

>Lennart97: Disambiguating links to Alcohol (link changed to Alcohol (chemistry); link changed to Alcohol (chemistry)) using DisamAssist.