this paper, aryldiazo sulfones are prepared from tandem sulfonylation/dehydrogenation reactions of arylhydrazines and sulfonyl chlorides. The transformations proceed well in the presence of catalytic CuSO4·5H2O, leading to aryldiazo sulfones in good to excellent yields. It is believed that this protocol represents a safe and convenient model for the synthesis of these versatile aryldiazo sulfones under
<sup><i>n</i></sup>Bu<sub>3</sub>P-Catalyzed Desulfonylative [3 + 2] Cycloadditions of Allylic Carbonates with Arylazosulfones to Pyrazole Derivatives
作者:Qi Zhang、Ling-Guo Meng、Kuai Wang、Lei Wang
DOI:10.1021/ol503735c
日期:2015.2.20
Highly efficient (Bu3P)-Bu-n-catalyzed desulfonylative [3 + 2] cycloadditions of allylic carbonates with arylazosulfones were developed for the synthesis of pyrazole derivatives. The reactions proceed smoothly under mild conditions to generate corresponding annulation products in good to excellent yields.