Synthesis of ortho-Nitrophenols with an Ester Functionality via Nitro Rearrangement
Kento Iwai1,2, Takumi Hamada1, Nagatoshi Nishiwaki1
1School of Engineering Science, Kochi University of Technology.
Abstract:
Although sigmatropic rearrangements have been widely reported, nitro group shifts have rarely been investigated. In this study, we investigated the synthesis of 4-ethoxycarbonyl-2-nitrophenols via the [1,3]-nitro shift. 4-Ethoxycarbonyl-4-nitrocyclohexanone, when subjected to I2-DMSO system, gave the 4-nitrocyclohexa-2,5-dienenone intermediate that undergoes [1,3]-nitro shift followed by aromatization to afford 4-ethoxycarbonyl-2-nitrophenols. Although there is a room for improvement in product yield and selectivity, the development of a reaction system that facilitates [1,3]-nitro shift from readily available starting materials is noteworthy.
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