Pyridine‐Catalysed Desulfonylative Addition of β‐Diketones to Arylazosulfones via Diaziridine Rearrangement
作者:Xin Ji、Ling‐Guo Meng、Hailong Xu、Lei Wang
DOI:10.1002/adsc.202001171
日期:2021.2.16
pyridine‐catalysed desulfonylative addition of β‐diketones to arylazosulfones was developed to obtain diazenyl β‐dicarbonyl compounds. The aryldiazenyl group was observed in the desired product from arylazosulfones, and this diazenylation reaction was achieved via a possible rearrangement process based on diaziridine ring cleavage. The scope of the protocol was investigated and a plausible mechanism was
<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.
Reactions of arylazosulfones with the conjugate bases of (tert-butoxycarbonyl)methyl and tosylmethyl isocyanide. Synthesis of substituted 1-arylimidazoles
The reactions of arylazosulfones 1 (ArN=NSO2Ar') with the potassium salts of (tert-butoxycarbonyl)methyl 2 and tosylmethyl isocyanide 3 in DMSO afford 4,5-bis(tert-butoxycarbonyl)-4 and 4-tosyl-1-arylimidazoles 5, respectively. Yields of imidazoles 4 and 5 vary from moderate to excellent depending on the nature both of Ar in 1 and of the nucleophile (2 or 3) employed. A comparison of the results obtained with those relevant to the reactions of the same nucleophiles with nitrosobenzene in analogous experimental conditions provides useful mechanistic indications on the transformation of 1 to 4 or 5. (C) 1997, Elsevier Science Ltd.