activation energies of various hydridetransferreactions was developed according to transition state theory using the Morse-type free energy curves of hydride donors to release a hydride anion and hydrideacceptors to capture a hydride anion and by which the activation energies of 187 typical hydride self-exchange reactions and more than thirty thousand hydride cross transferreactions in acetonitrile were
Unusual Reaction Constant for Hydride Transfer from a Carbanion to 9-Arylxanthyliums
作者:Fengrui Liu、Xiaoqing Zhu
DOI:10.1002/ejoc.201403023
日期:2014.11
The reaction constant (ρ) from the kinetics for hydride transfer from a carbanion (XH–) to 9-arylxanthylium ions (9-GPhXn+) in CH3CN was unusually negative. Thermodynamic analysis indicated that ρ for the simple hydride transfers (only involved with release and capture of a hydride anion) should be positive; this is in contrast to the kinetics results. Consequently, this reaction is not a simple hydride
Catalyst-free benzylic C(sp<sup>3</sup>)–H cross-coupling with organotrifluoroborates enabled by electrochemistry
作者:Chao Li、Ran Ding、Heng-Yi Guo、Shuang Xia、Lei Shu、Pei-Long Wang、Hongji Li
DOI:10.1039/d2gc02204d
日期:——
rare catalyst-free electrochemical cross-coupling of benzylic C–H bonds with organotrifluoroborates, which readily proceeds at room temperature and provides a unique protocol for forging C(sp3)–C(sp3), C(sp3)–C(sp2) and C(sp3)–C(sp) bonds. In particular, this work discloses the dual role of organotrifluoroborates serving both as a coupling partner and an electrolyte in C(sp3)–H functionalization.
A polybutadiene composition comprising a polybutadiene type polymer and a compound represented by the following formula (I):
1
wherein Ar
1
and Ar
2
each independently represent an aromatic ring, X and Y each independently represent an alkylene group having one or two carbon atoms, an oxygen atom or a carbonyl group, is provided; and thermal degradation of the polybutadiene type polymer can be prevented even in an air-free environment.
一种聚丁二烯组合物,由聚丁二烯类聚合物和下式(I)所代表的化合物组成:
1
其中 Ar
1
和 Ar
2
分别独立地代表一个芳香环,X 和 Y 分别独立地代表一个或两个碳原子的亚烷基、一个氧原子或一个羰基;即使在无空气环境中,也能防止聚丁二烯型聚合物的热降解。
Kovache, Annales de Chimie (Cachan, France), 1918, vol. <9> 10, p. 200