- Base-Promoted Direct Synthesis of Sulfinates from N -Sulfonyl-hydrazones under Metal-Free Conditions
-
A base-promoted direct synthesis of sulfinates from N -sulfonylhydrazones is described. Various N -sulfonylhydrazones, derived from aldehydes and ketones, are converted into the corresponding sulfinates in moderate to good yields. This protocol possesses
- Ji, Yuan-Zhao,Li, Hui-Jing,Luo, Dong-Hui,Wu, Qin-Xi,Wu, Yan-Chao
-
p. 755 - 762
(2020/02/25)
-
- Highly stereoselective synthesis of 1-cyanocyclopropane-carboxamides from 3-substituted-2-cyanoacrylamides with N-tosylhydrazones under metal-free conditions
-
A metal-free cyclopropanation of electron-deficient olefins 3-substituted-2-cyanoacrylamides with N-tosylhydrazones has been successfully developed. This strategy provide a simple route to the synthesis of very valuable 1-cyanocyclopropanecarboxamides wit
- Nie, Xufeng,Wang, Yachuan,Yang, Lijun,Yang, Zaijun,Kang, Tairan
-
p. 3003 - 3007
(2017/07/17)
-
- Metal-Free Ring-Expansion Reaction of Six-membered Sulfonylimines with Diazomethanes: An Approach toward Seven-Membered Enesulfonamides
-
A new metal-free, ring-expansion reaction of six-membered N-sulfonylimines with unstable diazomethanes, generated in situ from the N-tosylhydrazones, has been developed. This reaction delivers valuable seven-membered enesulfonamides by a Tiffeneau-Demjanov rearrangement and intramolecular proton transfer tautomerization process. Moreover, this ring-expansion reaction can be carried out in a one-pot fashion and scaled up to the gram scale by using aryl aldehydes, without the need to isolate the N-tosylhydrazone. A diazo thing: The title reaction between cyclic N-sulfonylimines and diazo compounds generated in situ from the N-tosylhydrazones is simple and functional-group tolerant. It thus delivers valuable seven-membered sulfonamides in up to 95 % yield. Moreover, this reaction can be carried out in one-pot starting from the aryl aldehydes, without the need to isolate the N-tosylhydrazone (right).
- Xia, An-Jie,Kang, Tai-Ran,He, Long,Chen, Lian-Mei,Li, Wen-Ting,Yang, Jin-Liang,Liu, Quan-Zhong
-
p. 1441 - 1444
(2016/02/12)
-
- N-Alkylation of tosylhydrazones in the presence of triphenylphosphine
-
An efficient N-alkylation reaction of tosylhydrazones was developed in the presence of triphenylphosphine; triphenylphosphine played a key role in the transformation. A range of N-alkylated tosylhydrazones were prepared in good to high yields.
- Kong, Yuanfang,Zhang, Wen,Tang, Meng,Wang, Haiming
-
supporting information
p. 7487 - 7491
(2013/08/23)
-
- Insights into sulfinate formation from tosyl hydrazides
-
Benzylation of 1,2-ditosylhydrazine in DMF under various basic conditions results in a benzyl sulfone via intermediary sulfinate formation, providing new insights and allowing practical conclusions to be drawn. The half-lives of 1,2-ditosylhydrazine and several monotosylated hydrazides with 1,1,3,3-tetramethylguanidine in DMSO have been determined by 1H NMR spectroscopy and are found to vary from a few minutes to several months. In the course of this work a benzylated, partly detosylated compound has been identified and a 1,1,3,3-tetramethyl guanidine-containing side-product characterized. A contradictory report is also commented on.
- Ragnarsson, Ulf,Grehn, Leif
-
scheme or table
p. 1045 - 1047
(2012/03/27)
-