Journal of The Chemical Society B: Physical Organic最新文献_第5页

Inductive and field effects in aromatic substitution. Part III. Comparison of the substituents X and CH2X in nitration 芳香取代的诱导效应和场效应。第三部分。取代基X与CH2X在硝化反应中的比较

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710000719

F. Sarlo, G. Grynkiewicz, A. Ricci, J. Ridd

引用次数: 1

Equilibria and kinetics in the isomerisation of o-formylbenzoic acid 邻甲酰苯甲酸异构化的平衡和动力学

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710002247

R. Bell, B. Cox, B. A. Timimi

引用次数: 9

The pyrolysis of 1,2-dichloroethane 1,2-二氯乙烷的热解

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710000577

K. A. Holbrook, R. Walker, W. Watson

{"title":"The pyrolysis of 1,2-dichloroethane","authors":"K. A. Holbrook, R. Walker, W. Watson","doi":"10.1039/J29710000577","DOIUrl":"https://doi.org/10.1039/J29710000577","url":null,"abstract":"The pyrolysis of 1,2-dichloroethane in a static system has been studied by g.l.c. analysis of the products and by pressure measurements in the temperature range 340–515 °C, surface:volume ratio range (1·32–37·4) cm–1, and with initial pressures from 0·3 to 300 Torr, in reaction vessels coated with pyrolytic carbon films.The major reaction is dehydrochlorination to vinyl chloride, but ethylene is also a primary reaction product. The ethylene yield is very small ( < 2% of the vinyl chloride) under conditions of low surface:volume ratio. It is concluded that the ethylene is produced by a concurrent heterogeneous dechlorination of 1,2-dichloroethane.At low surface:volume ratio the vinyl chloride produced is closely paralleled by the pressure increase and the reaction is found to have a high order (2·4–2·8) and activation energy (73 ± 3 kcal mol–1). The reaction is inhibited by additions of vinyl chloride, ethylene, and propene, and accelerated by added hydrogen chloride, oxygen, and chlorine. The radical-chain mechanism previously suggested by Barton and Howlett is discussed and modified to account for the experimental observations.The pressure–time curves obtained from experiments at high surface:volume ratio indicate that under these conditions the reaction is autocatalytic. The maximum rate corresponds to an order of 1·5 and an activation energy of 33·0 kcal mol–1. It is suggested that the autocatalysis is due to a heterogeneous initiation process involving adsorbed chlorine.","PeriodicalId":17268,"journal":{"name":"Journal of The Chemical Society B: Physical Organic","volume":"11 1","pages":"577-582"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86512274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Kinetics of thermal decomposition of acetic anhydride in flow and static systems 醋酸酐在流动和静态体系中的热分解动力学

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710001877

P. G. Blake, A. Speis

引用次数: 4

Structural implications of nuclear magnetic resonance and infrared investigations on 2-substituted 1,3,2-dioxaphosphorinan-2-ones 核磁共振和红外研究2-取代1,3,2-二磷-2- 1的结构意义

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710001454

D. W. White, G. K. Mcewen, R. D. Bertrand, J. Verkade

引用次数: 11

A theoretical study of the Edward–Lemieux effect (the anomeric effect). The stereochemical requirements of adjacent electron pairs and polar bonds Edward-Lemieux效应(球头效应)的理论研究。相邻电子对和极性键的立体化学要求

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710000136

S. Wolfe, A. Rauk, L. M. Tel, I. Csizmadia

{"title":"A theoretical study of the Edward–Lemieux effect (the anomeric effect). The stereochemical requirements of adjacent electron pairs and polar bonds","authors":"S. Wolfe, A. Rauk, L. M. Tel, I. Csizmadia","doi":"10.1039/J29710000136","DOIUrl":"https://doi.org/10.1039/J29710000136","url":null,"abstract":"Many data, collected from the literature, support the postulation of two general rules which describe the static and dynamic results of having in a molecule or generating in an intermediate adjacent electron pairs and/or polar bonds. In disagreement with current chemical intuition, structures which contain the maximum number of gauche-interactions between lone electron pairs or polar bonds represent energy minima and, frequently, the lowest minima. The stereochemical implications of the phenomenon are discussed, along with possible physical explanations. It is suggested that partitioning of the total energy of the system into attractive-dominant and repulsive-dominant interactions provides the most helpful framework for the construction of a physical picture of the phenomenon. The total energy and its components can be obtained by ab initio molecular quantum mechanical calculations.The only apparent exception to the phenomenon that has been found corresponds to a polar bond adjacent to two lone pairs (as in the case of two hetero-atoms attached to the same carbon atom). This exception, here termed the Edward–Lemieux effect, has been examined theoretically by an ab initio(Hartree–Fock) calculation using fluoromethanol as a model compound. The calculation has reproduced the Edward–Lemieux effect; the stable conformation has the C–F bond trans to one ‘electron pair’ and gauche to another, and the conformation in which the C–F bond bisects the ‘electron pairs’ is the energy maximum. The partitioning of the total energy into its components of attraction and repulsion and comparison of the results with other systems for which barriers to internal rotation have been obtained by ab initio methods reveals a similarity between fluoromethanol, hydrazine, hydroxylamine, and hydrogen peroxide. An interpretation of this result is provided in which an early suggestion by Lemieux and Chu is supported and the concept of ‘rabbit-ears’ is not.","PeriodicalId":17268,"journal":{"name":"Journal of The Chemical Society B: Physical Organic","volume":"8 1","pages":"136-145"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82838360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 55

Nitroxide radicals. Part X. Electron spin resonance spectra of [2,2]paracyclophanylene bisnitroxides 硝基氧自由基。第十部分[2,2]对环苯二烯双氮氧化物的电子自旋共振谱

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710001645

A. R. Forrester, R. Ramasseul

引用次数: 3

Conformational analysis of indan-1-ols 茚-1-醇的构象分析

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710001631

M. Hiscock, G. Porter

引用次数: 2

Symmetrically bifurcate hydrogen bonding. Part I. Bis-(β-acylvinyl)-amines 对称分叉氢键。第一部分:双-(β-酰基乙烯基)胺

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710000818

J. Dąbrowski, Z. Świstun

引用次数: 2

Reactions of carbonyl compounds in basic solutions. Part III. The mechanism of the alkaline hydrolysis of methyl 2-aroyl- and 2-acylbenzoates and related esters 羰基化合物在碱性溶液中的反应。第三部分。2-芳基甲酯和2-酰基苯甲酸甲酯及其相关酯的碱性水解机理

Journal of The Chemical Society B: Physical Organic Pub Date : 1971-01-01 DOI: 10.1039/J29710000149

K. Bowden, G. R. Taylor

引用次数: 8