Abstract An efficient and novel protocol for pyrazole synthesis has been developed by using fluoroboric acid as the acid catalyst. Simple and easily available 1,3-diketone and hydrazine derivatives are taken as the substrates for this purpose. The reaction entails mild reaction conditions and produces desired pyrazoles in good to excellent yields. Easy accessibility, easy handling, broad substrate
Copper-catalyzed C–N cross-coupling of arylboronic acids with N-acylpyrazoles
作者:Jin Zhang、Run-Ping Jia、Dong-Hui Wang
DOI:10.1016/j.tetlet.2016.06.044
日期:2016.8
A copper-catalyzed C–N bond forming reaction of arylboronicacids and N-acylpyrazoles was developed. This procedure used N-acetyl protected pyrazoles as starting material instead of free pyrazoles (NH). The reaction worked under neutral conditions and did not require any base or ligand. The reaction showed good functional group tolerance.
Herein an efficient and simple protocol was developed for the synthesis of pyrazoles and phthalazin-1(2H)-ones from a common precursor hydrazines catalyzed by nickelchloride. The reactions proceeded in water at room temperature. The advantages of the protocol are that both the medicinally important scaffolds could be synthesized with low-cost catalyst, green solvent, relatively lower reaction time