Sodium cyanoborohydride: Difference between revisions

Sodium cyanoborohydride
Names
	IUPAC name Sodium cyanoboranuide
	Other names Sodium cyanotrihydridoborate
Identifiers
CAS Number	25895-60-7 ;
3D model (JSmol)	Interactive image;
ECHA InfoCard	100.043.001
EC Number	247-317-2;
PubChem CID	5003444;
UNII	C4I8C58P9T ;
CompTox Dashboard (EPA)	DTXSID40894864 ;
	InChI InChI=1S/CH3BN.Na/c2-1-3;/h2H3;/q-1;+1;
	SMILES [BH3-]C#N.[Na+];
Properties
Chemical formula	Na[BH3(CN)]
Molar mass	62.84 g·mol−1
Appearance	white powder, hygroscopic
Density	1.083 g/cm (25°C)3
Melting point	242 °C (468 °F; 515 K) decomposes
Solubility in water	212 g/(100 mL) (29 °C)
Solubility	soluble in water, ethanol, diglyme, tetrahydrofuran, methanol ; slightly soluble in methanol ; insoluble in diethyl ether
Structure
Coordination geometry	4 at boron atom
Molecular shape	Tetrahedral at boron atom
Hazards
	Occupational safety and health (OHS/OSH):
Main hazards	Flammable solid, fatal if swallowed, in contact with skin or if inhaled; Contact with acids liberates very toxic gas; Contact with water liberates highly flammable gas
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H228, H300, H310, H314, H330, H410
Precautionary statements	P210, P260, P264, P273, P280, P284
NFPA 704 (fire diamond)	4 3 2
Threshold limit value (TLV)	5 mg/m3 (TWA)
Safety data sheet (SDS)	Sigma Aldrich
Related compounds
Other anions	Sodium borohydride
Related compounds	Lithium aluminium hydride
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

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Sodium cyanoborohydride is a chemical compound with the formula Na[B H₃(C N)]. It is a colourless salt used in organic synthesis for chemical reduction including that of imines and carbonyls. Sodium cyanoborohydride is a milder reductant than other conventional reducing agents.^[2]

Structure

Sodium cyanoborohydride is a salt. The cationic sodium ion, [Na]⁺, interacts with the anionic cyanoborohydride ion, [BH3(CN)]⁻. The anionic component of the salt is tetrahedral at the boron atom.

The electron-withdrawing cyanide substituent draws electron density away from the negatively charged boron; thus, reducing the electrophilic capabilities of the anionic component.^[2] This electronic phenomenon causes sodium cyanoborohydride to have more mild reducing qualities than other reducing agents. For example, Na[BH₃(CN)] is less reducing than its counterpart sodium borohydride, containing [BH₄]⁻.^[2]

Uses

Sodium cyanoborohydride is a mild reducing agent. It is generally used for the reduction of imines. These reactions occur <pH 7 because the iminium ions are the actual substrates.^[3]

Reductive amination, sometimes called the Borch reaction, is the conversion of a carbonyl into an amine through an intermediate imine.^[4] The carbonyl is first treated with ammonia to promote imine formation by nucleophilic attack. The imine is then reduced to an amine by sodium cyanoborohydride. This reaction works on both aldehydes and ketones. The carbonyl can be treated with ammonia, a primary amine, or a secondary amine to produce, respectively, 1°, 2°, and 3° amines.^[5]

Aromatic ketones and aldehydes can be reductively deoxygenated using sodium cyanoborohydride.^[6] This means that the carbonyl oxygen is being removed completely from the molecule. Deoxygenation using sodium cyanoborohydride is often done in the presence of trimethylsilyl chloride, or TMSCl.^[6]

Preparation

Sodium cyanoborohydride can be purchased from most chemical suppliers. It can be synthesized by combining sodium cyanide and borane tetrahydrofuran.^[7]

BH₃·thf + NaCN → NaBH₃CN + thf

Selectivity

Since sodium cyanoborohydride is a mild reducing agent, it gives good chemoselectivity for reaction with certain functional groups in the presence of others. For example, sodium cyanoborohydride is generally incapable of reducing amides, ethers, esters and lactones, nitriles, or epoxides.^[8] Therefore, it can selectively reduce some functionalities in the presence of others.

Some examples of selective reduction include:

Reduction of iminium ions in the presence of carbonyls^[8]
Reduction of aldehydes in the presence of ketones and esters.^[9]
Reduction of aldehydes in the presence of thioesters^[8]

The selectivity of this reducing agent makes it an important tool in organic synthesis. It allows for specific modifications to be made to complex organic molecules.

History

Georg Wittig was the first to synthesize a cyanoborohydride by treating lithium borohydride with hydrogen cyanide in 1951.^[8] The corresponding compound, sodium cyanoborohydride, was synthesized following a similar rationale by reacting sodium borohydride with hydrogen cyanide.^[10] The synthesis was later refined to use sodium cyanide and borane in THF making the process safer.^[10]

References

^ Sigma-Aldrich Co., Sodium cyanoborohydride. Retrieved on 2014-11-09.
^ ^a ^b ^c Baxter, Ellen W.; Reitz, Allen B. (9 January 2002). "Reductive Aminations of Carbonyl Compounds with Borohydride and Borane Reducing Agents". Organic Reactions: 1–714. doi:10.1002/0471264180.or059.01. ISBN 0-471-26418-0.
^ Hutchins, Robert O.; Hutchins, Marygail K.; Crawley, Matthew L.; Mercado-Marin, Eduardo V.; Sarpong, Richmond (2016). "Sodium Cyanoborohydride". Encyclopedia of Reagents for Organic Synthesis. pp. 1–14. doi:10.1002/047084289X.rs059.pub3. ISBN 978-0-470-84289-8.
^ Richard F. Borch (1988). "Reductive Amination with Sodium Cyanoborohydride: N,N-Dimethylcyclohexylamine". Organic Syntheses; Collected Volumes, vol. 6, p. 499.
^ Richard F. Borch and Mark D. Bernstein and H. Dupont Durst (1971). "Cyanohydridoborate Anion as a Selective Reducing Agent". J. Am. Chem. Soc. 93 (12): 2897–2904. doi:10.1021/ja00741a013.
^ ^a ^b Box, Vernon G. S.; Meleties, Panayiotis C. (1998-09-24). "Reductive, selective deoxygenation of acylbenzo[b]furans, aromatic aldehydes and ketones with NaBH3CN-TMSCl". Tetrahedron Letters. 39 (39): 7059–7062. doi:10.1016/S0040-4039(98)01519-6. ISSN 0040-4039.
^ Hui, Benjamin C. (October 1980). "Synthesis and properties of borohydride derivatives". Inorganic Chemistry. 19 (10): 3185–3186. doi:10.1021/ic50212a075. ISSN 0020-1669.
^ ^a ^b ^c ^d LANE, Clinton F. (1975). "Sodium Cyanoborohydride - A Highly Selective Reducing Agent for Organic Functional Groups". Synthesis. 1975 (3): 135–146. doi:10.1055/s-1975-23685. ISSN 0039-7881. S2CID 95157786.
^ Paul, Avishek; Shipman, Michael A.; Onabule, Dolapo Y.; Sproules, Stephen; Symes, Mark D. (2021-04-15). "Selective aldehyde reductions in neutral water catalysed by encapsulation in a supramolecular cage". Chemical Science. 12 (14): 5082–5090. doi:10.1039/D1SC00896J. ISSN 2041-6539. PMC 8179549. PMID 34163748.
^ ^a ^b Abdel-Magid, Ahmed F., ed. (1996-08-13). Reductions in Organic Synthesis: Recent Advances and Practical Applications. ACS Symposium Series. Vol. 641. Washington, DC: American Chemical Society. doi:10.1021/bk-1996-0641.ch001. ISBN 978-0-8412-3381-2.

This inorganic compound–related article is a stub. You can help Wikipedia by expanding it.

[1] Sigma-Aldrich Co., Sodium cyanoborohydride. Retrieved on 2014-11-09.

[Reitz-2002-2] Baxter, Ellen W.; Reitz, Allen B. (9 January 2002). "Reductive Aminations of Carbonyl Compounds with Borohydride and Borane Reducing Agents". Organic Reactions: 1–714. doi:10.1002/0471264180.or059.01. ISBN 0-471-26418-0.

[3] Hutchins, Robert O.; Hutchins, Marygail K.; Crawley, Matthew L.; Mercado-Marin, Eduardo V.; Sarpong, Richmond (2016). "Sodium Cyanoborohydride". Encyclopedia of Reagents for Organic Synthesis. pp. 1–14. doi:10.1002/047084289X.rs059.pub3. ISBN 978-0-470-84289-8.

[4] Richard F. Borch (1988). "Reductive Amination with Sodium Cyanoborohydride: N,N-Dimethylcyclohexylamine". Organic Syntheses; Collected Volumes, vol. 6, p. 499.

[5] Richard F. Borch and Mark D. Bernstein and H. Dupont Durst (1971). "Cyanohydridoborate Anion as a Selective Reducing Agent". J. Am. Chem. Soc. 93 (12): 2897–2904. doi:10.1021/ja00741a013.

[:0-6] Box, Vernon G. S.; Meleties, Panayiotis C. (1998-09-24). "Reductive, selective deoxygenation of acylbenzo[b]furans, aromatic aldehydes and ketones with NaBH3CN-TMSCl". Tetrahedron Letters. 39 (39): 7059–7062. doi:10.1016/S0040-4039(98)01519-6. ISSN 0040-4039.

[:1-7] Hui, Benjamin C. (October 1980). "Synthesis and properties of borohydride derivatives". Inorganic Chemistry. 19 (10): 3185–3186. doi:10.1021/ic50212a075. ISSN 0020-1669.

[:2-8] LANE, Clinton F. (1975). "Sodium Cyanoborohydride - A Highly Selective Reducing Agent for Organic Functional Groups". Synthesis. 1975 (3): 135–146. doi:10.1055/s-1975-23685. ISSN 0039-7881. S2CID 95157786.

[9] Paul, Avishek; Shipman, Michael A.; Onabule, Dolapo Y.; Sproules, Stephen; Symes, Mark D. (2021-04-15). "Selective aldehyde reductions in neutral water catalysed by encapsulation in a supramolecular cage". Chemical Science. 12 (14): 5082–5090. doi:10.1039/D1SC00896J. ISSN 2041-6539. PMC 8179549. PMID 34163748.

[:3-10] Abdel-Magid, Ahmed F., ed. (1996-08-13). Reductions in Organic Synthesis: Recent Advances and Practical Applications. ACS Symposium Series. Vol. 641. Washington, DC: American Chemical Society. doi:10.1021/bk-1996-0641.ch001. ISBN 978-0-8412-3381-2.

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@@ Line 1: / Line 1: @@
 {{chembox
-|Verifiedfields = changed
+| Verifiedfields = changed
-|Watchedfields = changed
+| Watchedfields  = changed
-|verifiedrevid = 438800960
+| verifiedrevid  = 438800960
-|Name = Sodium cyanoborohydride
+| Name           = Sodium cyanoborohydride
-|ImageFile = Sodium-cyanoborohydride-2D.png
+| ImageFile      = Sodium-cyanoborohydride-2D.png
-|ImageName = Sodium cyanoborohydride
+| ImageName      = Line-bond structure of sodium cyanoborohydride
-|OtherNames = Sodium cyanotrihydridoborate
+| OtherNames     = Sodium cyanotrihydridoborate
+| IUPACName      = Sodium cyanoboranuide
-|Section1={{Chembox Identifiers
+| Section1       = {{Chembox Identifiers
 |CASNo_Ref = {{cascite|correct|CAS}}
 |CASNo = 25895-60-7
@@ Line 17: / Line 18: @@
 |SMILES = [BH3-]C#N.[Na+]
 }}
-|Section2={{Chembox Properties
+| Section2       = {{Chembox Properties
 |Formula = {{chem2|Na[BH3(CN)]}}
 |Na=1|B=1|H=3|C=1|N=1
-|Appearance = white to off-white powder, [[hygroscopic]]
+|Appearance = white powder, [[hygroscopic]]
-|Density = 1.20 g/cm<sup>3</sup>
+|Density = 1.083 g/cm (25°C)<sup>3</sup>
 |Solubility = 212 g/(100 mL) (29 °C)
-|SolubleOther = soluble in [[diglyme]], [[tetrahydrofuran]], [[methanol]] <br> slightly soluble in [[methanol]] <br> insoluble in [[diethyl ether]]
+|SolubleOther = soluble in water, [[ethanol]], [[diglyme]], [[tetrahydrofuran]], [[methanol]] <br /> slightly soluble in [[methanol]] <br /> insoluble in [[diethyl ether]]
-|MeltingPtC = 241
+|MeltingPtC = 242
 |MeltingPt_notes = decomposes
  }}
-| Section3 = {{Chembox Structure
+| Section3       = {{Chembox Structure
 | Coordination = 4 at boron atom
 | MolShape = [[Tetrahedral molecular geometry|Tetrahedral]] at [[boron]] atom
   }}
-|Section7={{Chembox Hazards
+| Section7       = {{Chembox Hazards
 |ExternalSDS = Sigma Aldrich<ref>{{Sigma-Aldrich|sial|id=42077|name=Sodium cyanoborohydride |accessdate=2014-11-09}}</ref>
 |GHSPictograms = {{GHS02}}{{GHS05}}{{GHS06}}
@@ Line 41: / Line 42: @@
 |NFPA-R = 2
 |NFPA-S = <!--E NFPA code "E" is unknown, not accepted in [[Template:NFPA diamond]]. Please go to that talkpage if it is acceptable. DePiep 8 Nov 2014-->
-|MainHazards = Fatal if swallowed, in contact with skin or if inhaled<BR>Contact with acids liberates very toxic gas<BR>Contact with water liberates highly flammable gas
+|MainHazards = Flammable solid, fatal if swallowed, in contact with skin or if inhaled<br />Contact with acids liberates very toxic gas<br />Contact with water liberates highly flammable gas
 |TLV-TWA = 5 mg/m3
 }}
-|Section9={{Chembox Related
+| Section9       = {{Chembox Related
 |OtherAnions = [[Sodium borohydride]]
 |OtherCompounds = [[Lithium aluminium hydride]]
 }}
 }}
-'''Sodium cyanoborohydride''' is the [[chemical compound]] with the formula {{chem2|Na[BH3(CN)]|auto=1}}. It is a colourless salt, but commercial samples can appear tan. It is widely used in [[organic synthesis]] for the reduction of [[imine]]s. The salt tolerates aqueous conditions.<ref name=EROS>{{cite encyclopedia|authors=Robert O. Hutchins, MaryGail K. Hutchins, Matthew L. Crawley|title=Sodium Cyanoborohydride|encyclopedia=Encyclopedia of Reagents for Organic Synthesis|year=2007|pages=rs059.pub2 |publisher=John Wiley & Sons|doi=10.1002/047084289X.rs059.pub2|isbn=978-0471936237}}</ref>
+'''Sodium cyanoborohydride''' is a [[chemical compound]] with the formula {{chem2|Na[BH3(CN)]|auto=1}}. It is a colourless salt used in [[organic synthesis]] for [[Redox|chemical reduction]] including that of [[Imine|imines]] and [[Carbonyl group|carbonyls]]. Sodium cyanoborohydride is a milder reductant than other conventional [[Reducing agent|reducing agents]].<ref name="Reitz-2002">{{cite journal |last1=Baxter |first1=Ellen W. |last2=Reitz |first2=Allen B. |date=9 January 2002 |title=Reductive Aminations of Carbonyl Compounds with Borohydride and Borane Reducing Agents |journal=Organic Reactions |pages=1–714 |doi=10.1002/0471264180.or059.01 |isbn=0-471-26418-0}}</ref>
-==Use==
+== Structure ==
+Sodium cyanoborohydride is a salt. The [[cationic]] sodium ion, [Na]<sup>+</sup>, interacts with the [[Ion|anionic]] cyanoborohydride ion, [BH3(CN)]<sup>−</sup>. The anionic component of the salt is [[Tetrahedral molecular geometry|tetrahedral]] at the [[boron]] atom.
-Owing to the presence of the electron-withdrawing [[cyanide]] substituent, {{chem2|[BH3(CN)]−}} is less reducing than is [[sodium borohydride|{{chem2|[BH4]−}}]].<ref name="Reitz-2002">{{cite journal |last1=Baxter |first1=Ellen W. |last2=Reitz |first2=Allen B. |title=Reductive Aminations of Carbonyl Compounds with Borohydride and Borane Reducing Agents |journal=Organic Reactions |date=9 January 2002 |pages=1–714 |doi=10.1002/0471264180.or059.01|isbn=0471264180 }}</ref> As a mild reducing agent, it is used to convert [[imine]]s to [[amine]]s.<ref name="Christen-1997">{{cite book |last1=Christen |first1=Hans |last2=Meyer |first2=Gerd |title=Grundlagen der allgemeinen und anorganischen Chemie |date=1997 |publisher=Salle + Sauerländer |isbn=978-3-7935-5493-6 |page=824 |edition=1}}</ref>
+The [[Electron-withdrawing group|electron-withdrawing]] [[cyanide]] substituent draws electron density away from the negatively charged boron; thus, reducing the electrophilic capabilities of the anionic component.<ref name="Reitz-2002" /> This electronic phenomenon causes sodium cyanoborohydride to have more mild reducing qualities than other reducing agents. For example, Na[BH<sub>3</sub>(CN)] is less reducing than its counterpart [[sodium borohydride]], containing [BH<sub>4</sub>]<sup>−</sup>.<ref name="Reitz-2002" />
-It is especially favored for [[reductive amination]]s, wherein aldehydes or ketones are treated with an amine in the presence of this reagent:
-:{{chem2|R2CO + R'\sNH2 + Na[BH3(CN)] + CH3OH → R2CH\sNH\sR' + "Na[BH2(CN)(OCH3)]"}}{{cln|reason=Why Na[BH2(CN)(OCH3)] is between quotes???}}
-The reagent is typically used in excess. Selectivity is achieved at mildly basic solutions ([[pH]] 7–10).{{Citation needed|date=March 2023}} The reagent is ideal for [[reductive amination]]s ("Borch Reaction").<ref>{{OrgSynth|author=Richard F. Borch |year=1988|title=Reductive Amination with Sodium Cyanoborohydride: N,N-Dimethylcyclohexylamine|collvol=6|collvolpages=499|prep=CV6P0499}}</ref> In conjunction with tosylhydrazine, sodium cyanoborohydride is used in the reductive deoxygenation of [[ketones]].<ref name=EROS/>
+==Uses==
-==Structure and preparation==
+Sodium cyanoborohydride is a mild reducing agent. It is generally used for the reduction of [[imine]]s.  These reactions occur <pH 7 because the iminium ions are the actual substrates.<ref>{{cite book |doi=10.1002/047084289X.rs059.pub3 |chapter=Sodium Cyanoborohydride |title=Encyclopedia of Reagents for Organic Synthesis |date=2016 |last1=Hutchins |first1=Robert O. |last2=Hutchins |first2=Marygail K. |last3=Crawley |first3=Matthew L. |last4=Mercado-Marin |first4=Eduardo V. |last5=Sarpong |first5=Richmond |pages=1–14 |isbn=978-0-470-84289-8 }}</ref>
-The {{chem2|[BH3(CN)]−}} ion is [[Tetrahedral molecular geometry|tetrahedral]] at the [[boron]] atom, and it comprises the anionic component of the salt.
-The reagent is often purchased, although it can be prepared easily. One method involves combining [[sodium cyanide]] and [[borane]]. Another route entails treating sodium borohydride with [[mercury(II) cyanide]]. The commercial samples can be purified, but the yields of the reductive aminations do not improve.<ref>{{Cite journal | author = Richard F. Borch and Mark D. Bernstein and H. Dupont Durst | title = Cyanohydridoborate Anion as a Selective Reducing Agent | journal = [[J. Am. Chem. Soc.]] | pages = 2897–2904 | volume = 93 | issue = 12 | year = 1971 | doi = 10.1021/ja00741a013}}</ref>
+[[Reductive amination]], sometimes called the ''Borch reaction'', is the conversion of a [[Carbonyl group|carbonyl]] into an [[amine]] through an intermediate [[imine]].<ref>{{OrgSynth|author=Richard F. Borch|year=1988|title=Reductive Amination with Sodium Cyanoborohydride: N,N-Dimethylcyclohexylamine|collvol=6|collvolpages=499|prep=CV6P0499}}</ref> The carbonyl is first treated with ammonia to promote imine formation by nucleophilic attack. The imine is then reduced to an amine by sodium cyanoborohydride. This reaction works on both aldehydes and ketones. The carbonyl can be treated with [[ammonia]], a [[Amine|primary amine]], or a secondary amine to produce, respectively, 1°, 2°, and 3° amines.<ref>{{cite journal |author=Richard F. Borch and Mark D. Bernstein and H. Dupont Durst |year=1971 |title=Cyanohydridoborate Anion as a Selective Reducing Agent |journal=[[J. Am. Chem. Soc.]] |volume=93 |issue=12 |pages=2897–2904 |doi=10.1021/ja00741a013}}</ref>
+[[Aromatic compound|Aromatic]] [[Ketone|ketones]] and aldehydes can be reductively [[Deoxygenation|deoxygenated]] using sodium cyanoborohydride.<ref name=":0">{{cite journal |last1=Box |first1=Vernon G. S. |last2=Meleties |first2=Panayiotis C. |date=1998-09-24 |title=Reductive, selective deoxygenation of acylbenzo[b]furans, aromatic aldehydes and ketones with NaBH3CN-TMSCl |url=https://www.sciencedirect.com/science/article/pii/S0040403998015196 |journal=Tetrahedron Letters |volume=39 |issue=39 |pages=7059–7062 |doi=10.1016/S0040-4039(98)01519-6 |issn=0040-4039}}</ref> This means that the carbonyl oxygen is being removed completely from the molecule. Deoxygenation using sodium cyanoborohydride is often done in the presence of [[trimethylsilyl chloride]], or TMSCl.<ref name=":0" />
+== Preparation ==
+Sodium cyanoborohydride can be purchased from most chemical suppliers. It can be synthesized by combining [[sodium cyanide]] and [[borane tetrahydrofuran]].<ref name=":1">{{cite journal |last=Hui |first=Benjamin C. |date=October 1980 |title=Synthesis and properties of borohydride derivatives |url=https://pubs.acs.org/doi/abs/10.1021/ic50212a075 |journal=Inorganic Chemistry |language=en |volume=19 |issue=10 |pages=3185–3186 |doi=10.1021/ic50212a075 |issn=0020-1669}}</ref>
+:{{chem2|BH3*thf  +  NaCN  ->  NaBH3CN  +  thf}}
+== Selectivity ==
+Since sodium cyanoborohydride is a mild reducing agent, it gives good [[chemoselectivity]] for reaction with certain [[functional group]]s in the presence of others. For example, sodium cyanoborohydride is generally incapable of reducing [[amide]]s, [[ether]]s, [[ester]]s and [[lactone]]s, [[nitrile]]s, or [[epoxide]]s.<ref name=":2">{{cite journal |last=LANE |first=Clinton F. |date=1975 |title=Sodium Cyanoborohydride - A Highly Selective Reducing Agent for Organic Functional Groups |url=http://dx.doi.org/10.1055/s-1975-23685 |journal=Synthesis |volume=1975 |issue=3 |pages=135–146 |doi=10.1055/s-1975-23685 |s2cid=95157786 |issn=0039-7881}}</ref> Therefore, it can selectively reduce some functionalities in the presence of others.
+Some examples of selective reduction include:
+* Reduction of [[iminium]] ions in the presence of [[Carbonyl group|carbonyl]]s<ref name=":2" />
+* Reduction of [[aldehyde]]s in the presence of [[ketone]]s and esters.<ref>{{cite journal |last1=Paul |first1=Avishek |last2=Shipman |first2=Michael A. |last3=Onabule |first3=Dolapo Y. |last4=Sproules |first4=Stephen |last5=Symes |first5=Mark D. |date=2021-04-15 |title=Selective aldehyde reductions in neutral water catalysed by encapsulation in a supramolecular cage |journal=Chemical Science |language=en |volume=12 |issue=14 |pages=5082–5090 |doi=10.1039/D1SC00896J |issn=2041-6539 |pmc=8179549 |pmid=34163748}}</ref>
+* Reduction of aldehydes in the presence of [[thioester]]s<ref name=":2" />
+The selectivity of this reducing agent makes it an important tool in [[organic synthesis]]. It allows for specific modifications to be made to complex organic molecules.
+== History ==
+[[Georg Wittig]] was the first to synthesize a cyanoborohydride by treating [[lithium borohydride]] with [[hydrogen cyanide]] in 1951.<ref name=":2" /> The corresponding compound, sodium cyanoborohydride, was synthesized following a similar rationale by reacting [[sodium borohydride]] with [[hydrogen cyanide]].<ref name=":3">{{cite book |url=https://pubs.acs.org/doi/book/10.1021/bk-1996-0641 |title=Reductions in Organic Synthesis: Recent Advances and Practical Applications |date=1996-08-13 |publisher=American Chemical Society |isbn=978-0-8412-3381-2 |editor-last=Abdel-Magid |editor-first=Ahmed F. |series=ACS Symposium Series |volume=641 |location=Washington, DC |language=en |doi=10.1021/bk-1996-0641.ch001}}</ref> The synthesis was later refined to use [[sodium cyanide]] and [[borane]] in [[Tetrahydrofuran|THF]] making the process safer.<ref name=":3" />
 ==See also==