Diethylaluminium cyanide

Diethylaluminium cyanide
Names
	IUPAC name diethylalumanylformonitrile
	Other names Cyanodiethyl aluminium; (Cyano-κC)diethyl-aluminium; (Cyano-C)diethyl-aluminium; Cyanodiethyl-(7CI,8CI) aluminium; Cyanodiethylallane; Cyanodiethylaluminium; Diethylaluminium Cyanide;
Identifiers
CAS Number	5804-85-3 ;
ECHA InfoCard	100.024.873
PubChem CID	16683962;
CompTox Dashboard (EPA)	DTXSID301046472 ;
Properties
Chemical formula	(CH3CH2)2AlCN
Molar mass	111.124 g·mol−1
Appearance	Dark brown, clear liquid (1.0 mol/L in toluene)
Density	0.864 g/cm3 at (25 °C) (liquid)
Boiling point	162 °C (324 °F; 435 K) at 0.02 mmHg
Solubility in water	Reacts with water
Solubility	Benzene, Toluene, diisopropyl ether
Hazards
Flash point	7 °C (45 °F; 280 K) closed cup
	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

Diethylaluminium cyanide ("Nagata's reagent")^[2] is the organoaluminium compound with formula ((C₂H₅)₂AlCN)_n. This colorless compound is usually handled as a solution in toluene. It is a reagent for the hydrocyanation of α,β-unsaturated ketones.^[1]^[3]^[4]^[5]^[6]

Synthesis

Diethylaluminium cyanide was originally generated by treatment of triethylaluminium with a slight excess of hydrogen cyanide. The product is typically stored in ampoules because it is highly toxic. It dissolves in toluene, benzene, hexane and isopropyl ether. It undergoes hydrolysis readily and is not compatible with protic solvents.

n Et₃Al + n HCN → (Et₂AlCN)_n + n EtH

Structure

Diethylaluminium cyanide has not been examined by X-ray crystallography, although other diorganoaluminium cyanides have been. Diorganylaluminium cyanides have the general formula (R₂AlCN)_n, and they exist as cyclic trimers (n = 3) or tetramers (n = 4). In these oligomers, one finds AlCN---Al linkages. One compound similar to diethylaluminium cyanide is bis[di(trimethylsilyl)methyl]aluminium cyanide, ((Me₃Si)₂CH)₂AlCN, which has been shown crystallographically to exist as a trimer with the following structure:^[4]

trimeric bis[di(trimethylsilyl)methyl]aluminium cyanide

Bis(tert-butyl)aluminium cyanide, ^tBu₂AlCN exists as a tetramer in the crystalline phase:^[7]^[8]

tetrameric bis(tert-butyl)aluminium cyanide

Uses

Diethylaluminium cyanide is used for the stoichiometric hydrocyanation of α,β-unsaturated ketones. The reaction is influenced by the basicity of the solvent. This effect arises from the Lewis acidic qualities of the reagent.^[9] The purpose of this reaction is to generate alkylnitriles, which are precursors to amines, amides, carboxylic acids esters and aldehydes.

References

^ ^a ^b ^c "MSDS - 276863". Sigma-Aldrich. Retrieved December 9, 2012.
^ Nagata, W (1988). "Diethylaluminum cyanide". Organic Syntheses. VI: 307. doi:10.15227/orgsyn.052.0090.
^ Nagata, W. (1966). "Alkylaluminum cyanides as potent reagents for hydrocyanation". Tetrahedron Lett. 7 (18): 1913–1918. doi:10.1016/S0040-4039(00)76271-X.
^ ^a ^b Uhl, Werner; Schütz, Uwe; Hiller, Wolfgang; Heckel, Maximilian (1995). "Synthese und Kristallstruktur des trimeren [(Me₃Si)₂CH]₂Al—CN". Z. anorg. allg. Chem. 621 (5): 823–828. doi:10.1002/zaac.19956210521.
^ Wade, K.; Wyatt, B. K. (1969). "Reactions of organoaluminium compounds with cyanides. Part III. Reactions of trimethylaluminium, triethylaluminium, dimethylaluminium hydride, and diethylaluminium hydride with dimethylcyanamide". J. Chem. Soc.: 1121–1124. doi:10.1039/J19690001121.
^ Coates, G. E.; Mukherjee, R. N. (1963). "35. Dimethylaluminium cyanide and its gallium, indium, and thallium analogues; beryllium and methylberyllium cyanide". J. Chem. Soc.: 229–232. doi:10.1039/JR9630000229.
^ Uhl, W.; Matar, M. (2004). "Hydroalumination of nitriles and isonitriles" (PDF). Z. Naturforsch. B. 59 (11–12): 1214–1222. doi:10.1515/znb-2004-11-1239. S2CID 99001626.
^ Uhl, W.; Schütz, U.; Hiller, W.; Heckel, M. (2005). "Synthese und Kristallstruktur des trimeren [(Me₃Si)₂CH]₂Al—CN" (PDF). Z. Naturforsch. B. 60 (2): 155–163.
^ Nagata, W.; Yoshioka, M. (1988). "Diethylaluminum cyanide". Organic Syntheses; Collected Volumes, vol. 6, p. 436.

External links

Media related to Diethylaluminium cyanide at Wikimedia Commons

[MSDS-1] "MSDS - 276863". Sigma-Aldrich. Retrieved December 9, 2012.

[2] Nagata, W (1988). "Diethylaluminum cyanide". Organic Syntheses. VI: 307. doi:10.15227/orgsyn.052.0090.

[3] Nagata, W. (1966). "Alkylaluminum cyanides as potent reagents for hydrocyanation". Tetrahedron Lett. 7 (18): 1913–1918. doi:10.1016/S0040-4039(00)76271-X.

[Uhl_1995-4] Uhl, Werner; Schütz, Uwe; Hiller, Wolfgang; Heckel, Maximilian (1995). "Synthese und Kristallstruktur des trimeren [(Me₃Si)₂CH]₂Al—CN". Z. anorg. allg. Chem. 621 (5): 823–828. doi:10.1002/zaac.19956210521.

[5] Wade, K.; Wyatt, B. K. (1969). "Reactions of organoaluminium compounds with cyanides. Part III. Reactions of trimethylaluminium, triethylaluminium, dimethylaluminium hydride, and diethylaluminium hydride with dimethylcyanamide". J. Chem. Soc.: 1121–1124. doi:10.1039/J19690001121.

[6] Coates, G. E.; Mukherjee, R. N. (1963). "35. Dimethylaluminium cyanide and its gallium, indium, and thallium analogues; beryllium and methylberyllium cyanide". J. Chem. Soc.: 229–232. doi:10.1039/JR9630000229.

[7] Uhl, W.; Matar, M. (2004). "Hydroalumination of nitriles and isonitriles" (PDF). Z. Naturforsch. B. 59 (11–12): 1214–1222. doi:10.1515/znb-2004-11-1239. S2CID 99001626.

[8] Uhl, W.; Schütz, U.; Hiller, W.; Heckel, M. (2005). "Synthese und Kristallstruktur des trimeren [(Me₃Si)₂CH]₂Al—CN" (PDF). Z. Naturforsch. B. 60 (2): 155–163.

[9] Nagata, W.; Yoshioka, M. (1988). "Diethylaluminum cyanide". Organic Syntheses; Collected Volumes, vol. 6, p. 436.

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