Journal of The Chemical Society-perkin Transactions 1最新文献_第8页

The asymmetric Bischler–Napieralski reaction: preparation of 1,3,4-trisubstituted 1,2,3,4-tetrahydroisoquinolines 不对称Bischler-Napieralski反应:1,3,4-三取代1,2,3,4-四氢异喹啉的制备

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B106942J

M. Nicoletti, D. O'Hagan, A. Slawin

引用次数: 3

Synthesis of soluble halogenated aryloxy substituted indium phthalocyanines 可溶性卤代芳氧基取代酞菁铟的合成

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B107689M

M. Plater, Adam Jeremiah, G. Bourhill

引用次数: 10

15N NMR spectra, tautomerism and diastereomerism of 4,5-dihydro-1H-1,2,3-triazoles 1,2,3- 4,5-二氢- 1h -1,2,3-三唑的15N核磁共振波谱、互变异构和非对映异构

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B107326E

K. Banert, Jens Lehmann, H. Quast, G. Meichsner, D. Regnat, B. Seiferling

引用次数: 1

EPR and computational studies of the formation and beta-scission of cyclic and acyclic dialkoxyalkyl radicals 环和非环二氧烷基自由基形成和裂解的EPR和计算研究

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B106140M

Alistair J. Fielding, P. Franchi, B. P. Roberts, Teika M. Smits

{"title":"EPR and computational studies of the formation and beta-scission of cyclic and acyclic dialkoxyalkyl radicals","authors":"Alistair J. Fielding, P. Franchi, B. P. Roberts, Teika M. Smits","doi":"10.1039/B106140M","DOIUrl":"https://doi.org/10.1039/B106140M","url":null,"abstract":"EPR spectroscopy and density functional theory have been applied to study the formation and subsequent β-scission of a series of dialkoxyalkyl radicals. Abstraction of hydrogen by photochemically-generated tert-butoxyl radicals from acyclic acetals R1O(R2O)CHR3, and from cyclic analogues derived from diols, takes place mainly from the acetal carbon atom to give radicals of the type R1O(R2O)ĊR3 and relative rates of abstraction have been determined in competition experiments. When R3 \u0000= phenyl or vinyl, the activating influence of these substituents on hydrogen-atom abstraction is smaller than might be expected, probably because delocalisation of the unpaired electron on to the unsaturated group comes at the expense of planarisation at Cα, in opposition to the natural pyramidalising tendency of the two α-alkoxy groups. Absolute rate constants and Arrhenius \u0000activation parameters for β-scission of R1O(R2O)ĊR3 have been determined by a steady-state EPR method and the results can be understood in terms of angle-strain and stereoelectronic effects. β-Scission of selected cyclic dialkoxyalkyl radicals that carry a phenyl or vinyl substituent at the radical centre has been investigated using density functional theory at the UB3LYP/6-31G(d,p) level. Computed activation parameters are in good agreement with the experimental results, where comparison is possible. Both experiment and theory indicate that benzylic 2-phenyl-1,3-dioxan-2-yl radicals undergo β-scission more readily than the corresponding allylic 2-vinyl-1,3-dioxan-2-yl radicals.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"9 1","pages":"155-163"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81555639","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: 5

Inverse Wittig reaction of oxaphosphetenes formed by the [2+2] cycloaddition of arylphosphine oxides and dimethyl acetylenedicarboxylate (DMAD) 芳基膦氧化物与二甲基乙炔二羧酸酯(DMAD)[2+2]环加成形成的氧膦烯的逆Wittig反应

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B108675H

G. Keglevich, Henrietta Forintos, T. Körtvélyesi, L. Tőke,

引用次数: 11

Condensation of triformylmethane with adenosine: novel cyclic adducts derived from 1,3-dicarbonyl compounds 三甲酰甲烷与腺苷的缩合:从1,3-二羰基化合物中衍生的新型环状加合物

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B104790F

K. Neuvonen, N. Koissi, H. Lönnberg

引用次数: 1

Diastereocontrolled synthesis of hydroxylated lactams 羟基内酰胺的非对映控制合成

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B108056N

M. Andrews, A. Brewster, M. Moloney

引用次数: 2

Phenyl group acceleration of [1,4] carbon-to-oxygen silicon-mediated elimination–rearrangement in β-silyl sulfones. Synthesis of O -silylated cinnamyl alcohols β-硅基砜中[1,4]碳-氧-硅介导的消除重排的苯基加速。O -硅基化肉桂醇的合成

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B109805E

S. Menichetti, C. Stirling

引用次数: 2

Vibrational spectroscopy of a tetraureidocalix[4]arene based molecular capsule 四金枝[4]芳烃基分子胶囊的振动光谱研究

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B108055P

J. Dormann, A. Ruoff, J. Schatz, M. Vysotsky, V. Böhmer

{"title":"Vibrational spectroscopy of a tetraureidocalix[4]arene based molecular capsule","authors":"J. Dormann, A. Ruoff, J. Schatz, M. Vysotsky, V. Böhmer","doi":"10.1039/B108055P","DOIUrl":"https://doi.org/10.1039/B108055P","url":null,"abstract":"Structural models for self-assembled dimers composed of two urea calix[4]arenes which entrap benzene or cyclohexane are developed using Fourier transform infrared (FTIR) spectroscopy. Based on the host–guest ratio determined by 1H NMR spectroscopy in solution, and confirmed for the solid state by a thermogravimetric analysis, it is possible to prove by a comparison of the FTIR data of host, guest, complex and model compounds, that the capsule is held together by a cyclic array of weak and strong hydrogen bonds between the urea units attached at the wide rim of the calixarenes. The dimerization of the two urea units leads to a loss of symmetry, and an averaged C4 symmetrical arrangement is probable. Guest molecules, such as benzene or cyclohexane, are enclosed inside the container rotating fast on the IR timescale around a longitudinal axis of the guest. From the observed splitting of absorption bands upon dimerization and inclusion \u0000it follows that either two crystallographically independent types of capsules exist in the crystal lattice or that the guests are occupying two major orientations in the capsule. As indicated by a higher complexation induced shift for cyclohexane, this guest exhibits a tighter interaction with the host molecules compared to benzene.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"4 1","pages":"83-87"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87644734","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: 1

Reductive cleavage of N-substituted aromatic amides as tert-butyl acylcarbamates n -取代芳香酰胺还原裂解为叔丁基氨基甲酸酯

Journal of The Chemical Society-perkin Transactions 1 Pub Date : 2002-12-17 DOI: 10.1039/B107330N

U. Ragnarsson, L. Grehn, H. Maia, L. Monteiro

引用次数: 21