Regioselective synthesis of 2-aminophenols from N-arylhydroxylamines
Zhiwei Gao1, Zhiguo Hou1, Hongyin Gao1
1School of Chemistry and Chemical Engineering, Shandong University, Ji'nan, Shandong 250100, China. hygao@sdu.edu.cn.
Abstract:
A novel strategy for the synthesis of 2-aminophenols in the absence of metals and oxidants was described. The 2-aminophenols were efficiently obtained through a cascade [3,3]-sigmatropic rearrangement and in situ hydrolysis process by using readily available N-arylhydroxylamines and the in situ-generated methyl chlorosulfonate from commercially available sulfuryl chloride and methanol under mild conditions. This method could be scaled up and has a wide substrate scope with great functional group tolerance and high regioselectivity. The 2-aminophenol products could be readily converted into structurally diverse functional molecules in good yields under various conditions.
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