Sodium Hydride-Copper(II) Acetate-Sodium t-Pentoxide

NaH + Cu(OAc)2 + NaO-t-C5H11
(NaH)

[7646-69-7]  · HNa  · Sodium Hydride-Copper(II) Acetate-Sodium t-Pentoxide  · (MW 24.00) (Cu(OAc)2)

[142-71-2]  · C4H6CuO4  · Sodium Hydride-Copper(II) Acetate-Sodium t-Pentoxide  · (MW 181.65) (NaO-t-C5H11)

[14593-46-5]  · C5H11NaO  · Sodium Hydride-Copper(II) Acetate-Sodium t-Pentoxide  · (MW 110.15)

(a complex reducing agent (CRA) that converts aromatic halides to hydrocarbons; can act as a coupling agent1,2)

Physical Data: see Sodium Hydride and Copper(II) Acetate; the t-pentoxide salt is prepared in situ.

Solubility: sol THF, DME.

Preparative Methods: from NaH, t-pentanol, and Cu(OAc)2 in THF. Addition of t-pentanol begins at 40 °C, as it is very important not to exceed 45 °C throughout the process. After 3 h of stirring at 45 °C, the catalyst is ready for use.3,4

Handling, Storage, and Precautions: store under argon in airtight bottles; moisture sensitive. Use in a fume hood.

Reduction of Aromatic Halides.

The title reagent is an example of a series of complex reducing agents (CRAs) obtained by treating NaH and an alcohol (in this case, t-pentanol) with a metallic acetate salt (in this case, copper(II) acetate). These CRAs exhibit reducing abilities which can be varied by changing the solvent, the alkoxide, or the reaction temperature. In eq 1, reduction of 1-bromonaphthalene to the hydrocarbon is accompanied by coupling to produce 1,1-binaphthyl.

Both THF and DME can be used as solvent. In THF, reaction after 17 h yielded 60-65% naphthalene and 20% 1,1-binaphthyl. In DME, after 20 h, 80-85% naphthalene and 5-10% 1,1-binaphthyl were formed. With other salts (Co(OAc)2, Ni(OAc)2, Zn(OAc)2), hydrocarbon yields were 85-95% within 5 min-2 h, with no coupling product observed.

Reduction of Primary Alkyl Halides.

The reagent was not effective in the reduction of primary alkyl halides. When reacted with n-octyl bromide, it afforded mainly 1-octene along with small amounts (5-20%) of octane.

Related Reagents.

Nickel Complex Reducing Agents; Sodium Hydride; Sodium Hydride-Nickel(II) Acetate-Sodium t-Pentoxide; Sodium Hydride-Palladium(II) Acetate-Sodium t-Pentoxide; Zinc Complex Reducing Agents.


1. Brunet, J. J.; Vanderesse, R.; Caubere, P. JOM 1978, 157, 125.
2. Vanderesse, R.; Brunet, J.-J.; Caubere, P. JOC 1981, 46, 1270.
3. Brunet, J.-J.; Gallois, P.; Caubere, P. TL 1977, 3955.
4. Brunet, J.-J.; Gallois, P.; Caubere, P. JOC 1980, 45, 1937.

Edward J. Parish & Haoyu Qin

Auburn University, AL, USA



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