A new efficient and convenient approach towards the synthesis of pyrazole is described. The α,β-unsaturated cyanoesters were obtained from substituted benzaldehyde and ethyl cyanoacetate by reported methods. 1,5-Disubstituted pyrazoles were synthesized from α,β-unsaturated cyanoester and phenyl hydrazine using sodium ethoxide as a base in the presence of 10 mol % Cu(I) catalyst in high yields within 75-90 min under ultrasound irradiation at 60 ºC. The reaction rate is enhanced tremendously under ultrasound irradiation as compare to conventional methods with improved yields are recorded.
The regioselective 1,4-addition reactions of copper thiocyanate catalyzed Grignard reagents to the
substituted chalcones are reported. The homogeneous solution of dilithium tetrachloromanganate is
used to transmetallate magnesium by using manganese. It adds regio-selectively to substituted chalcone
derivatives and forms 1,4-addition products with higher yield under nitrogen atmosphere and at a
lower temperature. It have been observed that manganese from dilithium tetrachloromanganate reagent
replaces magnesium from Grignard reagent and adds regioselectively by 1,4-addition manner utilizing
copper thiocyanate as a catalyst. The course of the reaction in the absence of dilithium
tetrachloromanganate reagent was also studied and obtained a mixture of 1,2-addition and 1,4-addition
products. In presence of dilithium tetrachloromanganate reagent, a good regio-selectivity and higher
yield of desired 1,4-addition product were obtained. All the synthesized compounds were also evaluated
for their antibacterial activity against Staphylococcus aureus (Gram-positive), Escherichia coli (Gramnegative)
and antifungal activity against Aspergillus niger.
The regioselective 1,4-addition of CuSCN catalyzed Grignard reagents to the substituted coumarins
are reported. The Li2MnCl4 reagent is used to transmetallate magnesium by manganese. It adds
regioselectively to coumarins and forms 1,4-addition products with higher yield under the atmosphere
of nitrogen gas and at a lower temperature
The epoxides were obtained from substituted phenols and epichlorohydrin by reported methods. The regioselective ring opening of epoxides were studied in different solvents by reaction with Grignard’s reagent in presence of dilithium tetrachloromanganate.
The β-amino compounds were synthesized from α,β-unsaturated esters, nitriles and amine using water
as a solvent in the presence of 10 mol % Cu(I) catalyst in high yields within 2-5 min under ultrasound
irradiation at room temperature. The reaction rate was enhanced tremendously under ultrasound irradiation
as compared to conventional methods with improved yields have been recorded.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.