The first catalytic enantioselective C（sp）-C（sp^3） cross-coupling reaction between N-tosylhydrazones and trialkylsilylethynes in the presence of Cu（I） salts and chiral phosphoramidite ligands was developed. A se...The first catalytic enantioselective C（sp）-C（sp^3） cross-coupling reaction between N-tosylhydrazones and trialkylsilylethynes in the presence of Cu（I） salts and chiral phosphoramidite ligands was developed. A series of svnthetically interesting, functionalized alkynes were obtained with moderate to good enanttiselectivities （up to 83% ee）. Cu（ll） carbene migratory insertion is proposed to be the enantio-determining step. KEYWORDS C（sp）--C（sp^3） cross-coupling, metal carbene, asymmetric catalysis, Cu（I） catalysts, N-tosylhydrazones展开更多
Carbene transfer reactions play an important role in the field of organic synthesis because of their ability to construct a variety of molecules. Herein, we reported on blue light-induced cyclopropenizations of N-tosy...Carbene transfer reactions play an important role in the field of organic synthesis because of their ability to construct a variety of molecules. Herein, we reported on blue light-induced cyclopropenizations of N-tosylhydrazones in water, which avoids the use of expensive metal-based catalysts and toxic organic solvents. This metal-free and operationally simple methodology enable highly efficient cyclopropenizations, X-H insertion reactions, and cyclopropanation under mild reaction conditions.展开更多
A novel method for the synthesis of esters via reductive coupling of N-tosylhydrazones with carboxylic acids under metal-free conditions has been developed. Various functional groups were found to be tolerable under t...A novel method for the synthesis of esters via reductive coupling of N-tosylhydrazones with carboxylic acids under metal-free conditions has been developed. Various functional groups were found to be tolerable under the re- action conditions to afford low to good yields.展开更多
Synthesis of di-substituted aryl olefins via a Pd（0）-catalyzed cross-coupling reaction of biphenyl ketones/alde- hydes, tosylhydrazide, and aryl bromides （or benzyl halides） was developed. This methodology was ach...Synthesis of di-substituted aryl olefins via a Pd（0）-catalyzed cross-coupling reaction of biphenyl ketones/alde- hydes, tosylhydrazide, and aryl bromides （or benzyl halides） was developed. This methodology was achieved by one-pot two-step reactions involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with biphenyl ketones/aldehydes, followed by coupling with aryl bromides （or benzyl halides） in the presence of Pd（PPh3）4 and lithium t-butoxide to produce various di-substituted aryl olefins in moderate to good yields.展开更多
基金Acknowledgement The project is supported by the National Basic Research Program of China （973 Program, No. 2015CB856600）, the National Natural Science Foundation of China （Grant 21472004, 21332002） and the China Postdoctoral Science Foundation Funded Project （2015M5B0911）.
文摘The first catalytic enantioselective C（sp）-C（sp^3） cross-coupling reaction between N-tosylhydrazones and trialkylsilylethynes in the presence of Cu（I） salts and chiral phosphoramidite ligands was developed. A series of svnthetically interesting, functionalized alkynes were obtained with moderate to good enanttiselectivities （up to 83% ee）. Cu（ll） carbene migratory insertion is proposed to be the enantio-determining step. KEYWORDS C（sp）--C（sp^3） cross-coupling, metal carbene, asymmetric catalysis, Cu（I） catalysts, N-tosylhydrazones
基金supported by the National Natural Science Foundation of China (Nos. 8137325981573286, 8177357781602954)。
文摘Carbene transfer reactions play an important role in the field of organic synthesis because of their ability to construct a variety of molecules. Herein, we reported on blue light-induced cyclopropenizations of N-tosylhydrazones in water, which avoids the use of expensive metal-based catalysts and toxic organic solvents. This metal-free and operationally simple methodology enable highly efficient cyclopropenizations, X-H insertion reactions, and cyclopropanation under mild reaction conditions.
基金Acknowledgement The authors are thankful to the China Postdoctoral Science Foundation （No. 2011M500096）, and Natural Scientific Research Innovation Foundation in Harbin Institute of Technology （No. HIT.NSRIF 2010054）. L. Wu also would like to thank Harbin Institute of Technology for startup financial support.
文摘A novel method for the synthesis of esters via reductive coupling of N-tosylhydrazones with carboxylic acids under metal-free conditions has been developed. Various functional groups were found to be tolerable under the re- action conditions to afford low to good yields.
基金We gratefully acknowledge financial support of this work by the National Natural Science Foundation of China （No. 21563025）, and Shihezi University Training Programme for Distinguished Youth Scholars （No. 2014ZRKXJQ05）, and Start-Up Foundation for Young Scientists of Shihezi University （RCZX201408）.
文摘Synthesis of di-substituted aryl olefins via a Pd（0）-catalyzed cross-coupling reaction of biphenyl ketones/alde- hydes, tosylhydrazide, and aryl bromides （or benzyl halides） was developed. This methodology was achieved by one-pot two-step reactions involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with biphenyl ketones/aldehydes, followed by coupling with aryl bromides （or benzyl halides） in the presence of Pd（PPh3）4 and lithium t-butoxide to produce various di-substituted aryl olefins in moderate to good yields.
