Migration of double bonds in end-blocked linear olefinic compounds
作者:A. J. Hubert
DOI:10.1039/j39670000235
日期:——
The preparation and the isomerisation of some 1,12-diphenyldodec-6-enes are described. The migration of the double bond in the presence of triethylborane gives an equilibrium between all the positional isomers. The isomer with the double bond conjugated with the aromatic nucleus is preferred but substantial quantities of the other isomers are also present at equilibrium. The concentration of the “conjugated
Quinone Alkylation Using Organocadmium Reagents: A General Synthesis of Quinols
作者:Aaron Aponick、Jason D. McKinley、Jeffrey C. Raber、Carl T. Wigal
DOI:10.1021/jo972300d
日期:1998.4.1
Reactions of p-benzoquinone with organocadmiumreagents yield quinols, the result of quinone carbonyl monoalkylation. The reactions proceed in good yield and are devoid of bisaddition and hydroquinone byproducts. Quinone alkylations using this method show general applicability to p-benzoquinone as well as extended quinone systems using primary alkyl, secondary alkyl, and aryl reagents.
The synthesis of the seven isomeric methylchlorooctanoates is reported, in most cases for the first time, and their spectral characteristics are described and studied. Hypotheses are advanced to explain the abnormal spectral behaviour of some of them. The mass spectra show scrambling of hydrogen/chlorine and/or the chain carbons, as well as low ability to undergo the McLafferty rearrangement, in some
在大多数情况下,这是首次报道了七个异构体氯辛酸甲酯的合成,并对其光谱特性进行了描述和研究。假设被用来解释其中一些的异常光谱行为。在某些情况下,质谱显示氢/氯和/或链碳的加扰,以及进行麦克拉菲重排的能力低。给出了一套完整的13 C NMR参数,包括所有位置的取代基效应,发现除三个值外,系列中的各个位置都具有出色的相干性。
Influence of Positional Isomers on the Macroscale and Nanoscale Architectures of Aggregates of Racemic Hydroxyoctadecanoic Acids in Their Molecular Gel, Dispersion, and Solid States
作者:Shibu Abraham、Yaqi Lan、Ricky S. H. Lam、Douglas A. S. Grahame、Jennifer Jae Hee Kim、Richard G. Weiss、Michael A. Rogers
DOI:10.1021/la204412t
日期:2012.3.20
Inter/intramolecular hydrogen bonding of a series of hydroxystearic acids (HSAs) are investigated. Self-assembly of molecular gels obtained from these fatty acids with isomeric hydroxyl groups is influenced by the position of the secondary hydroxyl group. 2-Hydroxystearic acid (2HSA) does not form a molecular dimer, as indicated by FT-IR, and growth along the secondary axis is inhibited because the secondary hydroxyl
Mass spectrometry is the best physical method for the configurational assignment of E- and Z-3,5-dialkylcyclohexylidene acetic acid esters 1 and E- and Z-3-alkyl-2-alkenoates 2. The homoallylic cleavage resulting in the loss of the C-3 and C-5 alkyl groups from 1 and of the two δ-alkyls from 2 is a stereospecific process: the loss of the group which is adjacent to the carbonyl is significantly preferred