A facile one-pot synthesis of 2-aminothiazoles has been carried in PEG-400 as a greener medium at room temperature.This method avoids the use of lachrymatric a-bromoketones as well as the volatile,toxic organic solvents.
Silica chloride catalysted one pot cyclocondensation of aldehydes,ethyl acetoacetate and phenyl hydrazine leading to substituted pyrazoles has been reported.
A convenient synthesis of 6-amino-2H,4H-pyrano[2,3-F]pyrazole-5-carbonitriles has been accomplished by one pot four-component cyclocondensation of aromatic aldehydes（1a-o） malanonitrile（2）, ethyl acetoacetate（3）...A convenient synthesis of 6-amino-2H,4H-pyrano[2,3-F]pyrazole-5-carbonitriles has been accomplished by one pot four-component cyclocondensation of aromatic aldehydes（1a-o） malanonitrile（2）, ethyl acetoacetate（3）, and hydrazine hydrate（4） in freshly prepared deep eutectic solvent, DES（choline chloride：urea）. This protocol has afforded corresponding pyrano[2,3-F]pyrazoles in shorter reaction time with high yields, and it avoids the use of typical toxic catalysts and solvents.展开更多
文摘A facile one-pot synthesis of 2-aminothiazoles has been carried in PEG-400 as a greener medium at room temperature.This method avoids the use of lachrymatric a-bromoketones as well as the volatile,toxic organic solvents.
文摘Silica chloride catalysted one pot cyclocondensation of aldehydes,ethyl acetoacetate and phenyl hydrazine leading to substituted pyrazoles has been reported.
文摘A convenient synthesis of 6-amino-2H,4H-pyrano[2,3-F]pyrazole-5-carbonitriles has been accomplished by one pot four-component cyclocondensation of aromatic aldehydes（1a-o） malanonitrile（2）, ethyl acetoacetate（3）, and hydrazine hydrate（4） in freshly prepared deep eutectic solvent, DES（choline chloride：urea）. This protocol has afforded corresponding pyrano[2,3-F]pyrazoles in shorter reaction time with high yields, and it avoids the use of typical toxic catalysts and solvents.
