Molecules (Jun 2012)
Ring-Expansion Reaction of Oximes with Aluminum Reductants
Abstract
The ring-expansion reactions of heterocyclic ketoximes and carbocyclic ketoximes with several reductants such as AlHCl<sub>2</sub>, AlH<sub>3</sub> (alane), LiAlH<sub>4</sub>, LiAlH(O<em><sup>t</sup></em>Bu)<sub>3</sub>, and (MeOCH<sub>2</sub>CH<sub>2</sub>O)<sub>2</sub>AlH<sub>2</sub>Na (Red-Al) were examined. Among reductants, AlHCl<sub>2</sub> (LiAlH<sub>4</sub>:AlCl<sub>3</sub> = 1:3) in cyclopentyl methyl ether (CPME) has been found to be a suitable reagent for the reaction, and the rearranged cyclic secondary amines were obtained in good to excellent yields.
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