Xrthnty

Sodium cyanoborohydride
	;
Names;
	Other names; Sodium cyanotrihydridoborate;
Identifiers;
; CAS Number;	; ; 25895-60-7 Y; ;
; 3D model (JSmol);	; Interactive image; ;
; ECHA InfoCard;	; 100.043.001;
; EC Number;	247-317-2;
; ; PubChem CID; ;	; 20587905; ;
	; ; InChI; InChI=1S/CBN.Na/c2-1-3;/q-1;+1; ;
	; ; SMILES; [B-]C#N.[Na+]; ;
Properties;
; Chemical formula;	NaBH3CN ;
; Molar mass;	62.84 gmol−1
Appearance;	white to off-white powder, hygroscopic;
; Density;	1.20 g/cm3
; Melting point;	241 °C (466 °F; 514 K) decomposes;
; Solubility in water;	212 g/100 mL (29 °C);
; Solubility;	soluble in diglyme, tetrahydrofuran, methanol ; slightly soluble in methanol ; insoluble in diethyl ether;
Hazards;
Main hazards;	Fatal if swallowed, in contact with skin or if inhaled; Contact with acids liberates very toxic gas; Contact with water liberates highly flammable gas;
; Safety data sheet;	Sigma Aldrich
; GHS pictograms;	;
; GHS signal word;	Danger;
; GHS hazard statements;	; H228, H300, H310, H330, H314, H410;
; GHS precautionary statements;	; P210, P260, P264, P273, P280, P284;
; NFPA 704;	; ; ; ; ; 3; ; ; 4; ; ; 2; ; ; ;
; Threshold limit value;	5 mg/m3 (TWA);
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).;
	; N verify (what is YN ?);
	; Infobox references;
;	;

Sodium cyanoborohydride is the chemical compound with the formula NaBH₃CN. It is a colourless salt, but commercial samples can appear tan. It is widely used in organic synthesis for the reduction of imines. The salt tolerates aqueous conditions.^[2]

Use

Owing to the presence of the electron-withdrawing cyanide substituent, [B(CN)H₃]⁻ is far less reducing than is [BH₄]⁻, as found in sodium borohydride.^[3] As a mild reducing agent, it is especially used to convert imines to amines.

It is especially favored for reductive aminations, wherein aldehydes or ketones are treated with an amine in the presence of this reagent:

R₂CO + R'NH₂ + NaBH₃CN + CH₃OH → R₂CH-NHR' + "NaCH₃OBH₂CN"

The reagent is typically used in excess. Selectivity is achieved at mildly basic solutions (pH 7-10). The reagent is ideal for reductive aminations ("Borch Reaction").^[4] In conjunction with tosylhydrazine, sodium cyanoborohydride is used in the reductive deoxygenation of ketones.^[2]

Structure and preparation

The tetrahedral anion BH₃(CN)⁻ comprises the salt.

The reagent is invariably 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.^[5]

References

^ Sigma-Aldrich Co., Sodium cyanoborohydride. Retrieved on 2014-11-09.

^ ^a^b Robert O. Hutchins, MaryGail K. Hutchins, Matthew L. Crawley (2007). "Sodium Cyanoborohydride". Encyclopedia of Reagents for Organic Synthesis. John Wiley & Sons. doi:10.1002/047084289X.rs059.pub2.CS1 maint: Uses authors parameter (link).mw-parser-output cite.citationfont-style:inherit.mw-parser-output .citation qquotes:"""""""'""'".mw-parser-output .citation .cs1-lock-free abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .citation .cs1-lock-subscription abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registrationcolor:#555.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration spanborder-bottom:1px dotted;cursor:help.mw-parser-output .cs1-ws-icon abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center.mw-parser-output code.cs1-codecolor:inherit;background:inherit;border:inherit;padding:inherit.mw-parser-output .cs1-hidden-errordisplay:none;font-size:100%.mw-parser-output .cs1-visible-errorfont-size:100%.mw-parser-output .cs1-maintdisplay:none;color:#33aa33;margin-left:0.3em.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-formatfont-size:95%.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-leftpadding-left:0.2em.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-rightpadding-right:0.2em

^ Ellen W. Baxter, Allen B. Reitz Reductive Aminations of Carbonyl Compounds with Borohydride and Borane Reducing Agents in Organic Reactions, 2002, John Wiley and Sons. doi:10.1002/0471264180.or059.01

^ Richard F. Borch (1988). "Reductive Amination with Sodium Cyanoborohydride: N,N-Dimethylcyclohexylamine". Organic Syntheses.; Collective Volume, 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.

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

[EROS-2] Robert O. Hutchins, MaryGail K. Hutchins, Matthew L. Crawley (2007). "Sodium Cyanoborohydride". Encyclopedia of Reagents for Organic Synthesis. John Wiley & Sons. doi:10.1002/047084289X.rs059.pub2.CS1 maint: Uses authors parameter (link).mw-parser-output cite.citationfont-style:inherit.mw-parser-output .citation qquotes:"""""""'""'".mw-parser-output .citation .cs1-lock-free abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .citation .cs1-lock-subscription abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registrationcolor:#555.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration spanborder-bottom:1px dotted;cursor:help.mw-parser-output .cs1-ws-icon abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center.mw-parser-output code.cs1-codecolor:inherit;background:inherit;border:inherit;padding:inherit.mw-parser-output .cs1-hidden-errordisplay:none;font-size:100%.mw-parser-output .cs1-visible-errorfont-size:100%.mw-parser-output .cs1-maintdisplay:none;color:#33aa33;margin-left:0.3em.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-formatfont-size:95%.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-leftpadding-left:0.2em.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-rightpadding-right:0.2em

[3] Ellen W. Baxter, Allen B. Reitz Reductive Aminations of Carbonyl Compounds with Borohydride and Borane Reducing Agents in Organic Reactions, 2002, John Wiley and Sons. doi:10.1002/0471264180.or059.01

[4] Richard F. Borch (1988). "Reductive Amination with Sodium Cyanoborohydride: N,N-Dimethylcyclohexylamine". Organic Syntheses.; Collective Volume, 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.

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Xrthnty

Sodium cyanoborohydride

Contents

Use

Structure and preparation

See also

References

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Names

Other names Sodium cyanotrihydridoborate
Identifiers
CAS Number	25895-60-7^Y
3D model (JSmol)	Interactive image
ECHA InfoCard	100.043.001
EC Number	247-317-2
PubChem CID	20587905
InChI InChI=1S/CBN.Na/c2-1-3;/q-1;+1
SMILES [B-]C#N.[Na+]
Properties
Chemical formula	NaBH₃CN
Molar mass	62.84 gmol⁻¹
Appearance	white to off-white powder, hygroscopic
Density	1.20 g/cm³
Melting point	241 °C (466 °F; 514 K) decomposes
Solubility in water	212 g/100 mL (29 °C)
Solubility	soluble in diglyme, tetrahydrofuran, methanol slightly soluble in methanol insoluble in diethyl ether
Hazards
Main hazards	Fatal if swallowed, in contact with skin or if inhaled Contact with acids liberates very toxic gas Contact with water liberates highly flammable gas
Safety data sheet	Sigma Aldrich^[1]
GHS pictograms
GHS signal word	Danger
GHS hazard statements	H228, H300, H310, H330, H314, H410
GHS precautionary statements	P210, P260, P264, P273, P280, P284
NFPA 704	3 4 2
Threshold limit value	5 mg/m3 (TWA)
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).
N verify (what is ^YN ?)
Infobox references