34672-83-8Relevant academic research and scientific papers
Peculiarities of the reaction of 2,2,6,6-tetramethylpiperidin-1-oxyl with Cp2TiEtCl
Matkovskii,Chernaya
, p. 2755 - 2759 (1996)
The reaction of 2,2,6,6-tetramethylpiperidin-1-oxyl (1) with Cp2TiEtCl (2) has been studied. The consumption of 1 and evolution of gaseous products (ethane, ethylene) proceed with autoacceleration. Increasing the 1 : 2 molar ratio leads to inhibition of the autoacceleration. The fact that the yield of ethane is higher than that of ethylene indicates that the reaction proceeds via SR2 substitution of the ethyl group in Cp2TiEtCl for radical 1. The mechanism of the substitution is synchronous. A kinetic model of the reaction has been proposed and substantiated.
Synthesis of 4-Acylpyrazoles from Saturated Ketones and Hydrazones Featured with Multiple C(sp3)-H Bond Functionalization and C-C Bond Cleavage and Reorganization
Tian, Miaomiao,Shi, Xiaonan,Zhang, Xinying,Fan, Xuesen
, p. 7363 - 7372 (2017/07/26)
In this paper, an efficient and convenient one-pot synthesis of diversely substituted 4-acylpyrazole derivatives via copper-catalyzed one-pot cascade reactions of saturated ketones with hydrazones is reported. Mechanistically, the formation of the title compounds involves the in situ formation of an enone intermediate through the dehydrogenation of a saturated ketone and the [2 + 3] cyclization of the enone with hydrazone followed by an aromatization-driven C-C bond cleavage and reorganization. To our knowledge, this is the first example in which the biologically and pharmaceutically important yet otherwise difficult-to-obtain 4-acylpyrazole derivatives are directly prepared from saturated ketones and hydrazones featured with multiple aliphatic C-H bond functionalization and C-C bond cleavage and reorganization. Compared with literature methods, this novel process has advantages such as simple and economical starting materials, a sustainable oxidant, excellent regioselectivity, and good efficiency.
