interactions between the carbonyls and a methoxyl or a chlorogroup and are discussed from the electron-accepting ability of the carbonyl group and the electron-donating ability of the methoxyl and the chlorogroups. An aldehyde group was apparently less able to interact with electron-donors than a ketone. This apparent anomaly was discussed from the intramolecular dipolar interactions.
已经制备了在三苯乙烯系统的 1-位带有甲氧基或氯基团并在 9-位带有取代的羰基甲基的化合物,以通过 1 H NMR 光谱检查旋转异构体的群体。甲氧基化合物有利于±sc 构象,而p 构象在氯化合物中相对有利。结果表明羰基与甲氧基或氯基之间存在吸引相互作用,并从羰基的受电子能力和甲氧基和氯基的给电子能力进行讨论。与酮相比,醛基与电子供体的相互作用显然更弱。从分子内偶极相互作用讨论了这种明显的异常。
BUTTRESSING EFFECT IN OPPOSITE DIRECTION
作者:Gaku Yamamoto、Masahiko Suzuki、Michinori Oki
DOI:10.1246/cl.1980.1523
日期:1980.12.5
Rotational barrier in 1,2,3,4-tetrachloro-9-(1,1-dimethyl-2-phenylethyl)triptycene was 1.8 kcal/mol lower than that in the corresponding 1,4-dichloro derivative. This apparently anomalous “reverse” buttressing effect may be originated from the tilting of the 9-substituent away from the peri-chloro group in this highly congested system.
Restricted Rotation Involving the Tetrahedral Carbon. XI. Barriers to Rotation and Conformational Preferences of Substituted 9-Isopropyltriptycenes
作者:Fumio Suzuki、Michinori Oki、Hiroshi Nakanishi
DOI:10.1246/bcsj.47.3114
日期:1974.12
composition of which is almost 1 : 1 : 1. Repulsive nonbonding interaction is a decisive factor to determine the conformationalpreference. Approximate methods for line shape analysis of two methyl groups in an isopropyl group are discussed. Activation energies for rotation about the C9-Cpr bond increase with the increase in the size of 1-substituent except for the methyl group. The smaller effective size
How Do Ethane-Type Molecules Avoid Eclipsing When Forced as Such? The Case of 7,8,9,10-Tetrachloro-1,1-dimethyl-1,2,6,10b-tetrahydro-6,10b-<i>o</i>-benzenoaceanthrylene
The molecular structure of the title compound was determined by X-ray crystallography. To avoid the eclipsing interactions between the two methyl groups at the 1-position and the triptycene skeleton, the molecule exhibited several unusual bond lengths and bond angles. The benzene rings in the molecule were also deformed from planarity.
标题化合物的分子结构是通过 X 射线晶体学确定的。为了避免 1 位上的两个甲基与三庚烯骨架之间的黯然作用,分子呈现出几种不同寻常的键长和键角。分子中的苯环也发生了平面变形。
Congeneric, Chlorinated, Brominated And/Or Iodised, Fluorinated Aromatic Compounds Comprising Two Benzol Rings In Their Basic Structure, Method For Their Production And Use Thereof
申请人:Liu Huiling
公开号:US20070298501A1
公开(公告)日:2007-12-27
Congeneric, halogenated, fluorinated aromatic compounds
where A and B are each phenyl radicals, L=oxygen atom, sulfur atom or alkylene radical and p=0 or 1; processes for their preparation and their use.