Key Words: Boron halides; Lewis acidity; Principle of hard and soft acids and bases 1 引言 酸和碱是化学中最常用的概念。定义酸和碱有多种方法,如Arrenius 的酸碱电离理论、Brönsted 和Lowry 分别提出的酸碱质子理论以及Lewis 的酸碱电子理论。其中Lewis 于1923 年提出的电子对 受-授概念得到化学工作者...
Lewis acidity of boron trihalides; Significance of the ab initio calculations; Formation of a van der Waals bond; Evidence for conformational equilibrium; Influence of chlorination of the boron halide on complexation enthalpy.vanderVekenB.J.
According to calculations and experimental findings, the Lewis acidity of the CX3+ homologues (X=F–I) versus fluoride is reversed in comparison to that of the isoelectronic boron halides BX3, and decreases from CF3+ to CI3+.关键词:
The Lewis acidity of Molecules 2018, 23, 189 4 of 13 pair of Zn(C6F5)2/MTBD exhibited much higher activity in the polymerization of lactide and much Mloowleceurletse2m01p8,e2r3a,t1u8r9e dependence compared with the Lewis adduct Zn(C6F5)2/DMAP. And a pos4soibf 1le3 bMiofluecnuclet...
This invention relates to an improvement in a low-pressure storage and delivery system for gases having Lewis acidity, particularly hazardous specialty gases such as BF3
In order to avoid “over reactions” during the modification of inert C(sp3)-F bonds in saturatedgem-difluoroalkanes (1), we reduced the Lewis acidity of the Al-based promoters. We observed that such “controllable reactions” stopped at the defluorinative elimination or F-Cl exchange/elimina...
In most cases B/P-based FLPs with the acidity of the boron atoms enhanced by fluorinated groups have been applied [1], [2], [3], [5], but a variety of systems has been developed recently in which e.g. carbenes, amines or sulfur atoms are the basic components [1], [2], [3]...
There are many applications of chloroaluminate(III) ILs, such as electrode positions, which are not directly related to their Lewis acidity. The primary use of chloroaluminates(III) as Lewis acids is in catalysis; they are used directly as Lewis acidic catalysis (for example Diels–Alder reaction...
C.; Coley, S. M.; Yoder, C. H. The effect of the halide on the Lewis acidity of organotin halides. J. Organomet. Chem. 1990, 389, 295-300.Spencer JN, Ganunis T, Zafar A, Eppley H, Otter JC, Coley SM, Yoder CH (1990) J Organomet Chem 389:295...
Bismuth(III) halidesLewis acidsAlcohol conversionDFTS Ni mechanismThe Lewis acidity of BiX 3 (X=Cl, Br, I) is explored using density-functional theory (DFT) studies of simple complexes with various alcohol and carbonyl substrates. The calculated relative energies of the complexes follow the trend...