Reactions of complex metal hydrides of copper with alkyl halides, enones, and cyclic ketones
Journal
Journal of Organic Chemistry
Journal Volume
43
Journal Issue
2
Pages
183-188
Date Issued
1978
Author(s)
Abstract
A series of stable complex metal hydrides of copper of composition LinCuHn+1 (n=1-5), prepared by the reaction of LiAlH4 with the corresponding lithium methylcuprates in diethyl ether, has been allowed to react with selected alkyl halides, enones, and cyclic ketones in both diethyl ether and THF. It has been shown that the different hydrides exhibit different regioselectivities toward enones and different stereoselectivities toward cyclic ketones. These data support the integrity of each hydride as a single compound rather than a physical mixture. Tetrahydrofuran-soluble Li4CuH5 has been shown to be the most reactive of the complex metal hydrides of copper toward alkyl halides in that this hydride reduced 1-iodo-, 1-bromo-, and 1-chlorodecane in 100, 100, and 99% yields, respectively. The complex metal hydrides of copper reduce enones predominantly 1, 4 (Li2CuH3, 96%) or 1, 2 (Li4CuHs, 95%), depending on the hydride. In most cases, the complex metal hydrides of copper reduce 4-tert-butylcyclohexanone predominantly from the axial side, as in the case of LiAlH4. Other cyclohexanones are reduced by the complex metal hydrides of copper similarly to LiAlH4, except with less selectivity. © 1978, American Chemical Society. All rights reserved.
Type
journal article