- Direct C-H Alkenylation of Functionalized Pyrazoles
-
We have developed inter- and intramolecular C-H alkenylation reactions of pyrazoles. The catalyst, derived from Pd(OAc)2 and pyridine, enabled the oxidative alkenylation of pyrazoles containing a variety of functional groups at the C4 position.
- Han, Su Jin,Kim, Hyun Tae,Joo, Jung Min
-
p. 689 - 698
(2016/01/27)
-
- Halogenation of pyrazoles using N-halosuccinimides in CCl4 and in water
-
Reaction of pyrazoles with N-halosuccinimides (NXS, X=Br, Cl) in either CCl4 or water gave 4-halopyrazoles in excellent yields. The reaction was carried out under mild conditions and did not require any catalysts or special precautions. The reaction provides an efficient method for 4-C halogenation of pyrazoles. Copyright Taylor & Francis Group, LLC.
- Zhao, Zhi-Gang,Wang, Zhong-Xia
-
p. 137 - 147
(2007/10/03)
-
- Enzymatic Halogenation of Pyrazoles and Pyridine Derivatives
-
Pyrazole, 1-methylpyrazole and 3-methylpyrazole are chlorinated by the enzyme chloroperoxidase from Caldariomyces fumago, in the presence of potassium chloride and hydrogen peroxide at pH 2.7, yielding the corresponding 4-chloro derivatives in good yields.A 4H-pyrazole is proposed as an intermediate in this reaction. 2-Aminopyridine was converted regiospecifically by the same enzyme into 2-amino-3-chloropyridine, and 8-hydroxyquinoline gave its 5,7-dibromo-derivatives in very good yield when bromide ion was used as halide substrate.
- Franssen, M. C. R.,van Boven, H. G.,van der Plas, H. C.
-
p. 1313 - 1316
(2007/10/02)
-