- Synthesis and: In vitro evaluation of naphthalimide-benzimidazole conjugates as potential antitumor agents
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A series of novel naphthalimide-benzimidazoles was designed and synthesized for the first time and studied for their effect on antiproliferative activity. Some of these compounds possessed good antitumor activity towards the tested cancer cell lines. Noticeably, (diethylamino)ethyl 15 and (dimethylamino)ethyl 23 derivatives displayed superior antiproliferative activity towards human cancer cell lines with MG-MID GI50 values of 1.43 and 1.83 μM, respectively. Preliminary investigation revealed that compounds 15 and 23 might bind with ct-DNA through the intercalation mode which is responsible for potent bioactivity. Moreover, transportation behaviour indicated that these molecules could efficiently bind to and be carried by bovine albumin, and the hydrogen bonding and hydrophobic interactions played important roles in interaction with serum albumin.
- Singh, Iqubal,Luxami, Vijay,Paul, Kamaldeep
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Read Online
- Aromatic ring liquid crystal compound and liquid crystal composition and application thereof
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The invention relates to an aromatic ring liquid crystal compound, a liquid crystal composition and an assembly suitable for a microwave region and a millimeter wave region of a high-frequency technology or an electromagnetic spectrum, and particularly a phase shifter and a microwave array antenna. The liquid crystal composition provided by the invention at least comprises a compound represented by a general formula I. The liquid crystal composition provided by the invention is good in stability, high in response speed and wide in liquid crystal phase temperature range.
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Paragraph 0116-0118; 0121-0122; 0192-0195
(2021/05/29)
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- Exploring the nitro group reduction in low-solubility oligo-phenylenevinylene systems: Rapid synthesis of amino derivatives
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A small series of amino oligo-phenylenevinylenes (OPVs) were successfully synthesized from their nitro-analogs in a rapid, simple, and highly efficient fashion employing a sodium sulfide/pyridine system as a reducing agent. In this research, classic and sustainable reduction methodologies including NH4HCO2/Zn and a choline chloride/tin (II) chloride deep eutectic solvent (DES) were also evaluated, showing degradation products, incomplete reactivity, and product isolation difficulties in all cases. The straightforward Na2S/pyridine synthetic protocol proved to maintain the E-E stereochemistry of the OPV backbone that has been previously assembled by the Mizoroki–Heck cross-coupling reaction. Also, the optoelectronic properties were determined and discussed, considering the amino group insertion in these conjugated systems as a contribution for future construction of novel materials with applications in supramolecular electronics, light harvesting, and photocatalysis.
- Acelas, Mauricio,Sierra, Andrés Felipe,Sierra, César A.
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supporting information
p. 1335 - 1352
(2020/03/04)
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- Preparation method of high-purity 3-bromo -9- phenyl carbazole
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The invention discloses a preparation method of high-purity 3-bromine-9-phenylcarbazole, and belongs to the field of synthesis of organic chemicals. The method comprises the following steps: (1) conducting a nitratlon reaction on benzene dibromide to prepare an intermediate, that is, 1,4-dibromo-2-nitrobenzene; (2) enabling 1,4-dibromo-2-nitrobenzene and diphenylamine to have an Ullmann coupling reaction to prepare an intermediate, that is, (4-bromine-2-nitrobenzophenone) diphenylamine; (3) enabling the intermediate, that is, (4-bromine-2-nitrobenzophenone) diphenylamine to have a reduction reaction to prepare an intermediate, that is, (4-bromine-2-aminophenyl) diphenylamine; and (4) enabling the intermediate, that is, (4-bromine-2-aminophenyl) diphenylamine, to have a diazotization ring closing reaction to prepare 3-bromine-9-phenylcarbazole. 3-bromine-9-phenylcarbazole prepared through the method is used in the fields of OLED photoelectric materials, medicines, dyes, pesticides and the like, and is an important carbazole intermediate; the reaction operation is simple, the cost of the raw materials is low, the yield is relatively high, and the quality is high; and moreover, the process of removing dibromo in the traditional preparation method is avoided, and the production convenience is greatly improved.
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Paragraph 0059-0061; 0067-0069; 0074-0076
(2020/02/29)
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- Method for synthesizing dibromobenzene -2,5- 1,4- diiodo benzene (by machine translation)
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The synthetic method disclosed by the invention comprises 1,4 - the following steps: the, synthesis method disclosed by. the, invention has a good industrial production prospect, 1,4 - in the prior, art that, the raw materials are firstly, 2,5 - subjected to a nitrification step and then subjected to 2,5 - an iodine, generation step to generate 2,5 - the second bromo,4-diiodo benzene 1,4 . (by machine translation)
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Paragraph 0008; 0039-0041; 0048-0050; 0057-0059
(2020/01/12)
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- Effective synthesis of benzimidazoles-imidazo[1,2-a]pyrazine conjugates: A comparative study of mono-and bis-benzimidazoles for antitumor activity
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A novel series of 6-substituted-8-(1-cyclohexyl-1H-benzo[d]imidazole-6-yl)imidazo[1,2-a]pyrazine and 6-substituted-8-(1-benzyl-1H-benzo[d]imidazole-6-yl)imidazo[1,2-a]pyrazine is first time synthesized and screen in vitro biological activity for 60 human cancer cell lines representing nine different cancer types. Derivatives 10 and 36 show antitumor activity for all tested cell lines, display comparable full panel mean-graph midpoint growth inhibition (MG_MID GI50) values of 2.10 and 2.23 μM, respectively. Furthermore, these derivatives show strong binding interactions with DNA and bovine serum albumin (BSA), studied through absorption, emission, and circular dichroism techniques. These spectroscopic studies reveal that imidazo[1,2-a]pyrazine-benzimidazoles 10 and 36, intercalate with ct-DNA as a leading interaction for fundamental biologically significant effects, with monobenzimidazole show better activity than bisbenzimidazole. These experiments have confirmed that the imidazo[1,2-a]pyrazine and benzimidazole moieties are efficient pharmacophores to trigger binding to DNA. These compounds have also interacted with bovine serum albumin protein that demonstrating high values of binding constant.
- Singh, Iqubal,Luxami, Vijay,Paul, Kamaldeep
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p. 546 - 561
(2019/08/01)
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- Synthetic method of 2,5-dibromo-p-phenylenediamine
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The invention discloses a synthetic method of 2,5-dibromo-p-phenylenediamine. According to the method, the 2,5-dibromo-p-phenylenediamine is synthesized from a compound shown as I, namely, p-dibromobenzene serving as a starting material. By adopting the synthetic method of the 2,5-dibromo-p-phenylenediamine disclosed by the invention, the 2,5-dibromo-p-phenylenediamine can be effectively synthesized. Moreover, the synthetic method has the advantages of high synthesis efficiency, safe production, simple process operation, short production period and the like, so that the method is more suitablefor large-scale and industrialized production of the 2,5-dibromo-p-phenylenediamine.
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Paragraph 0081-0089; 0114-0121; 0143-0150; 0175-0182
(2018/10/26)
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- A compound 5, 8 - II (3, 4 - ethylene dioxy thienyl) - quinoline synthesis method
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The invention discloses a synthetic method of 5,8-bi(3,4-ethylenedioxy thienyl)-quinoline. The method comprises the steps of with 3,4-ethylenedioxy thienyl (EDOT) and p-dibromobenzene as substrates, brominating hydrogen at the position 2 of EDOT by using N-bromosuccinimide in the presence of tetrahydrofuran and acetic acid; performing nitrification on p-dibromobenzene, and performing Skraup reaction on a product obtained through reduction to generate 5,8-dibromo quinoline; enabling a product obtained by performing Grignard reaction on brominated EDOT to react with 5,8-dibromo quinoline under the catalytic action of nickel chloride to generate 5,8-bi(3,4-EDOT)-quinoline; performing electrochemical characterization of dyeing properties of the product. The synthetic method is simple and feasible, and has industrial prospects.
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Paragraph 0033; 0034; 0038; 0039; 0043; 0044
(2017/07/04)
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- PROCESS FOR THE PREPARATION OF ORGANIC HALIDES
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The present invention provides a halo-de-carboxylation process for the preparation of organic chlorides, organic bromides and mixtures thereof, from their corresponding carboxylic acids, using a chlorinating agent selected from trichloroisocyanuric acid (TCCA), dichloroisocyanuric acid (DCCA), or combination thereof, and a brominating agent.
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Paragraph 00122
(2017/08/01)
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- Donor-acceptor conjugated polymers based on thieno[3,2-b] indole (TI) and 2,1,3-benzothiadiazole (BT) for high efficiency polymer solar cells
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A universal synthetic strategy toward thieno[3,2-b]indole (TI) derivatives was developed. Three conjugated polymers (PTIBT, PTITBT and PTIDTBT) containing N-alkyl-TI as the donor units, 2,1,3-benzodiathiazole (BT) as the acceptor units and thiophene as the spacers were synthesized. The thiophene spacers have a dramatic impact on the physical and electrochemical properties of these copolymers. These polymer donors were used for the fabrication of bulk heterojunction polymer solar cells (PSCs). Preliminarily, power conversion efficiencies (PCEs) based on the device structure of ITO/PEDOT:PSS/polymer:PC71BM/Ca/Al exhibit a large distinction (1.61% for PTIBT, 5.83% for PTITBT and 1.79% for PTIDTBT) at optimal device fabrication conditions. The device based on PTITBT:PC71BM (1:3, w/w) shows the best PCE of 5.83% (Voc = 0.69 V, Jsc = 13.92 mA cm-2, FF = 61.8%), which represents one of the best performances among PCDTBT analogues. In addition, the Jsc of 13.92 mA cm-2 is also among the highest Jsc values of all PCDTBT analogues. On the basis of our results, one can conclude that incorporating TI and its derivatives into donor-acceptor conjugated polymers is a feasible and effective way to develop novel donor materials for high efficiency PSC applications.
- Huang, Hongyan,Qiu, Meng,Li, Quan,Liu, Shuli,Zhang, Xinzhen,Wang, Zheng,Fu, Nina,Zhao, Baomin,Yang, Renqiang,Huang, Wei
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p. 5448 - 5460
(2016/07/06)
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- Polymer-based fluorescence sensor incorporating thiazole moiety for direct and visual detection of Hg2+ and Ag+
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A thiazole-based conjugated polymer was synthesized by the polymerization reaction of 4,7-dibromo-2-methylbenzo[d]thiazole with 1,4-diethynyl-2,5-bis(octyloxy)benzene via Pd-catalyzed Sonogashira coupling reaction. The conjugated polymer emits bright green fluorescence and exhibits 'turn-off' fluorescent quenching responses towards both Hg2+ and Ag+ over other cations, such as Li+, K+, Ca2+, Mg2+, Ba2+, Zn2+, Cd2+, Co2+, Ni2+, Pb2+, Cu2+, Al3+ and Fe3+. More importantly, the color change of this polymer solution could be clearly observed by the naked eyes upon the addition of Hg2+ (green to colorless) and Ag+ (green to yellow), indicating that this thiazole-based conjugated polymer material could be used as a colorimetric sensor for directly visual detection of Hg2+ and Ag+.
- Li, Fei,Meng, Fandian,Wang, Yuxiang,Zhu, Chengjian,Cheng, Yixiang
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supporting information
p. 1700 - 1704
(2015/03/31)
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- Influence of the benzo[d]thiazole-derived π-bridges on the optical and photovoltaic performance of D-π-A dyes
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New metal-free organic sensitizers containing a benzo[d]thiazole or phenyl unit as the π-conjugated system, a triphenylamine as an electron donor, and a cyanoacrylic acid moiety as an electron acceptor were synthesized and used for dye-sensitized solar cells. Photophysical and electrochemical properties of these dyes were investigated, and their performances as sensitizers in solar cells were measured. The introduction of a benzo[d]thiazole unit into the molecular structure resulted in a high incident photon-to-current conversion efficiency (more than 70%) from 340 nm to 600 nm. One solar cell containing a benzo[d]thiazole unit, produced a η of 5.85% (JSC = 10.63 mA cm-2, VOC = 0.72 V, and ff = 0.77) under 100 mW cm -2 simulated AM 1.5 G solar irradiation.
- Ci, Zhenhua,Yu, Xiaoqiang,Bao, Ming,Wang, Chaolei,Ma, Tingli
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p. 619 - 625
(2013/03/14)
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- Synthesis of symmetrical dinitro-and diamino-substituted Troeger's base analogues
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This report describes a new synthetic approach to symmetrical diamino-substituted Troeger's base analogues, allowing the synthesis of 1,7-, and 4,10-diamino derivatives with no additional substituents and of 3,9-diamino derivative with methyl groups in the 1-, 4-, 7-and 10-positions. The synthesis uses regioselective nitration of dihalo-substituted-or tetrahalo-substituted Troeger's bases followed either by hydrogenation of the nitro functions accompanied by removal of halogen atoms or alternatively by chemoselective reduction of nitro groups to obtain the dihalo-diamino- substituted Troeger's base analogues. The 2,8-diamino derivatives, not accessible by this approach, can be prepared by Buchwald-Hartwig amination of the 2,8-dibromo-substituted Troeger's bases.
- Sturala, Jiri,Cibulka, Radek
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supporting information
p. 7066 - 7074
(2013/02/21)
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- 4,7-Diaryl indole-based fluorescent chemosensor for iodide ions
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Simple and selective indole based fluorescent sensors for iodide anions are reported. A series of 4,7-diaryl indole derivatives (DAIs) are designed and synthesized using Suzuki coupling. These DAIs shows significant changes in UV-vis and fluorescent intensity only with addition of iodides and not with other anions. The ability of these DAIs to function as selective iodide chemosensor is reported.
- Rathikrishnan, Krishnaswamy R.,Indirapriyadharshini, Vellore K.,Ramakrishna, Seeram,Murugan, Rajendiran
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scheme or table
p. 4025 - 4030
(2011/06/26)
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- Silver-catalyzed decarboxylative halogenation of carboxylic acids
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Decarboxylative halogenation of carboxylic acids catalyzed by silver carbonate is reported. ortho-Nitrobenzoic acids react with copper(II) chloride or bromide in DMF/DMSO at 130-140 °C leading to the corresponding aryl halides in moderate to good yields.
- Luo, Yong,Pan, Xiaolin,Wu, Jie
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supporting information; experimental part
p. 6646 - 6648
(2011/02/21)
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- ALKYL-SUBSTITUTED 3' COMPOUNDS HAVING 5-HT6 RECEPTOR AFFINITY
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The present disclosure provides compounds having affinity for the 5-HT6 receptor which are of the formula (I): wherein R1, R2, Ar, m and n are as defined herein. The disclosure also relates to methods of preparing such compounds, compositions containing such compounds, and methods of use thereof.
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Page/Page column 33
(2010/02/17)
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- CONDENSED HETEROCYCLIC COMPOUNDS HAVING 5-HT6 RECEPTOR AFFINITY
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The present disclosure provides compounds having affinity for the 5-HT6 receptor which are of the formula (I) wherein R1, A, B, D, E, G, Q, Ar, n, m, and p are as defined herein. The disclosure also relates to methods of preparing such compounds, compositions containing such compounds, and methods of use thereof.
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Page/Page column 94
(2010/04/03)
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- ACYCLIC COMPOUNDS HAVING 5-HT6 RECEPTOR AFFINITY
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The present disclosure provides compounds having affinity for the 5-HT6 receptor which are of the formula (I): wherein R1, R2, R5, Q, G, Ar, m, and n are as defined herein. The disclosure also relates to methods of preparing such compounds, compositions containing such compounds, and methods of use thereof.
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Page/Page column 62
(2010/03/02)
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- 4'-AMINO CYCLIC COMPOUNDS HAVING 5-HT6 RECEPTOR AFFINITY
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The present disclosure provides compounds having affinity for the 5-HT6 receptor which are of the formula (I): formula (I) wherein Cy is selected from formula (Il) and wherein R1, R2, R3, Q, G, Ar, m, n and p are as defined herein. The disclosure also relates to methods of preparing such compounds, compositions containing such compounds, and methods of use thereof.
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Page/Page column 112
(2010/04/06)
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- PYRROLIDINE-SUBSTITUTED AZAINDOLE COMPOUNDS HAVING 5-HT6 RECEPTOR AFFINITY
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The present disclosure provides compounds having affinity for the 5-HT6 receptor which are of the formula (I): wherein R1, R2, A, B, D, E, G, Ar, and n are as defined herein. The disclosure also relates to methods of preparing such compounds, compositions containing such compounds, and methods of use thereof.
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Page/Page column 44
(2010/02/17)
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- 3' SUBSTITUTED COMPOUNDS HAVING 5-HT6 RECEPTOR AFFINITY
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The present disclosure provides compounds having affinity for the 5-HT6 receptor which are of the formula (I): wherein Q, R1, R4, m and Ar are as defined herein. The disclosure also relates to methods of preparing such compounds, compositions containing such compounds, and methods of use thereof.
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Page/Page column 129
(2009/04/25)
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- Synthesis of macrocyclic molecular rods as potential electronic devices
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The design and synthesis of the macrocycles 1 and 2 as model compounds for the investigation of negative differential conductance phenomena in molecular junctions are reported. The macrocycles 1 and 2 comprise a molecular rod subunit consisting of three ethynyl-linked phenyl rings. While the rotational freedom along the rod axis of both terminal phenyl rings is limited by the macrocyclic frame, the central phenyl ring is revolving. The rod substructure is terminally functionalized with acetyl-protected thiol groups to enable its immobilization between gold contacts. The central phenyl ring is functionalized with one and two nitro groups for 1 and 2, respectively. The nitro groups are of particular importance as i) both macrocycles are model compounds to investigate a hypothetical intramolecular interaction of the nitro group with the opposite macrocyclic subunits and ii) the nitro group(s) result in limited thermal stability of the compounds due to the intramolecular rearrangement to macrocycles comprising isatogen subunits. These highly functionalized macrocycles have been assembled by acetylene scaffolding strategies in combination with functional group transformation chemistry. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Blaszczyk, Alfred,Chadim, Martin,Von Haenisch, Carsten,Mayor, Marcel
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p. 3809 - 3825
(2007/10/03)
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- Synthesis of terphenyl oligomers as molecular electronic device candidates
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Six functionalized bis(phenylene ethynylene)-p,p-terphenyls (BPETs) have been synthesized as potential molecular electronic devices. The molecules containing mono- and dinitro terphenyl cores, were rationally designed based on the electronic properties recently found in oligo(phenylene ethynylene)s (OPEs). From our understanding of the conductance properties in OPEs, improvement of electronic properties may be possible by using BPETs due to a higher rotational barrier between the central aromatic rings of the compounds prepared here. BPETs cores were functionalized with nitro groups and with different metallic adhesion moieties (alligator clips) to provide new compounds for testing in the nanopore and planar testbed structures.
- Maya, Francisco,Tour, James M.
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- Cyclic compounds and uses thereof
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Compounds of general formula (1) R1—X1—W—X2—Z1—Z2—R2 or salts thereof, exhibiting preventive and therapeutic effects against HIV infectious diseases wherein R1is an optionally substituted five- or six-membered ring group; X1is a free valency or the like; W is a divalent group represented by, e. g., general formula (2) (wherein A and B are each an optionally substituted five- to seven-membered ring; E1and E4are each optionally substituted carbon or the like; E2and E3are each oxygen or the like; and a and b are each a single bond or a double bond); X2is a divalent group constituting a straight chain moiety; Z1is a divalent cyclic group or the like; Z2is a free valency or the like; and R2is optionally substituted amino or the like.
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- Sulfonamide-containing indole compounds
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The present invention creates a novel antiangiogenic agent and provides an antitumor agent which shows high safety as compared with conventional antitumor agents, has a sure effect and is able to be administered for a long period. That is, it provides an indole compound represented by the following formula (I), its pharmacologically acceptable salt or hydrates thereof. In the formula, R1 represents hydrogen atom, a halogen atom or cyano group; R2 and R3 are the same as or different from and each represents hydrogen atom, a C1-C4 lower alkyl group or a halogen atom; R4 represents hydrogen atom or a C1-C4 lower alkyl group; and the ring A represents cyanophenyl group, aminosulfonylphenyl group, aminopyridyl group, aminopyrimidyl group, a halopyridyl group or cyanothiophenyl group, provided that the case where all of R1, R2 and R3 are hydrogen atoms, where both R2 and R3 are hydrogen atoms or where the ring A is aminosulfonyl group and both R1 and R2 are halogen atoms is excluded. Further, when the ring A is cyanophenyl group, 2-amino-5-pyridyl group or a 2-halo-5-pyridyl group and R1 is cyano group or a halogen atom, at least one of R2 and R3 should not be a hydrogen atom.
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- CYCLIC COMPOUNDS AND USES THEREOF
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Compounds of general formula (1) or salts thereof, exhibiting preventive and therapeutic effects against HIV infectious diseases wherein R1 is an optionally substituted five- or six-membered ring group; X1 is a free valency or the like; W is a divalent group represented by, e. g., general formula (2) (wherein A and B are each an optionally substituted five-to seven-membered ring; E1 and E4 are each optionally substituted carbon or the like; E2 and E3 are each oxygen or the like; and a and b are each a single bond or a double bond); X2 is a divalent group constituting a straight chain moiety; Z1 is a divalent cyclic group or the like; Z2 is a free valency or the like; and R2 is optionally substituted amino or the like.
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- Phenylene ethynylene diazonium salts as potential self-assembling molecular devices
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(matrix presented) Functionalized diazonium salts for molecular electronic devices are prepared by the reaction of the corresponding anilines with NOBF4 in sulfolane-acetonitrile solvent.
- Kosynkin, Dmitry V.,Tour, James M.
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p. 993 - 995
(2007/10/03)
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- Lanthanide(III) triflates as recyclable catalysts for atom economic aromatic nitration
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Lanthanide(III) triflates catalyse (1-10 mol%) the nitration of a range of simple aromatic compounds in good to excellent yield using stoichiometric quantities of 69% nitric acid; the only by-product is water and the catalyst can be readily recycled by simple evaporation.
- Waller, Francis J.,Barrett, Anthony G. M.,Braddock, D. Christopher,Ramprasad, Dorai
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p. 613 - 614
(2007/10/03)
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- Ozone-mediated reaction of polychlorobenzenes and some related halogeno compounds with nitrogen dioxide: A novel non-acid methodology for the selective mononitration of moderately deactivated aromatic systems
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In the presence of ozone and preferably methanesulfonic acid as catalyst, polychlorobenzenes undergo selective mononitration with nitrogen dioxide at low temperatures, giving the corresponding polychloronitrobenzenes, in most cases in nearly quantitative yields.
- Suzuki,Mori,Maeda
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p. 841 - 845
(2007/10/02)
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- Imine-bridged planar poly(p-phenylene) derivatives for maximization of extended π-conjugation. The common intermediate approach
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Described are two approaches to planar conjugated poly(p-phenylene) (PPP) derivatives. The first approach, involving lactam bridges, was unsuccessful due to the insolubility of the 6(5H)-phenanthridinonyl moieties. The second approach, which utilized imine bridges, worked excellently since the compounds were generally soluble and the bridge formations were highly efficient. The main PPP backbone was synthesized via Pd(0)-catalyzed coupling of an arylbis(boronic ester) with an aryl dibromide. Imine bridges, which are formed by exposure of the polymer to trifluoroacetic acid or HCl, force the consecutive units into planarity. The bridging units are sp2 hybridized, thus allowing for greater π-electron flow between the consecutive phenyl units. The polymers, upon planarization, exhibit enormous bathochromic shifts of 210-240 nm. The optical spectra of the planar systems are compared to that of the parent nonplanarized polymers, oligo(p-phenylenes), and PPP. When the bridges were n-dodecyl- or n-octylphenyl-substituted, the fully planar structures could be made into flexible free-standing films. Additionally, an improved method is described in which a common intermediate, an aryl dibromo diacyl halide, could be used to prepare both the A and B units for the AB-type step growth polymerization. In one case, a selective alkylation or arylation of the acyl portions was accomplished using lower order cyanocuprates or Pd(0)-catalyzed ketone formation. For the second monomer, a bis-Curtius rearrangement, in the presence of tert-butyl alcohol, converted both carbonyl moieties to BOC protected amines.
- Lamba, Jaydeep J. S.,Tour, James M.
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p. 11723 - 11736
(2007/10/02)
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- Magnetic susceptibilities of organic compounds: Part V - Influence of substituents on diamagnetic susceptibilities of disubstituted and trisubstituted benzenes
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The magnetic susceptibilities of a number of triads of isomeric disubstituted benzenes have been determined, choosing the compounds in such a way that the substituents are present in the following combinations: (i) two electron-releasing substituents, (ii) a halogeno and an electron-releasing substituent, (iii) a halogeno and an electron-attracting substituent, and (iv) two halogeno substituents.The data show that for types (i), (ii) and (iv), the ortho isomers have the highest magnetic susceptibilities, the susceptibilities decreasing in the order: ortho > meta > para; for type (iii), the meta-isomers have the highest susceptibilities, the susceptibilities decreasing in the order: meta > para > ortho.The diamagnetic susceptibilities of some isomeric trisubstituted benzenes have also been determined and the data reveal that the susceptibility is the highest where the crowding of substituents is the highest (1,2,3-isomer) and lowest where the substituents are staggered and least crowded (1,3,5-isomer).Another observation made in the case of trisubstituted benzene is the applicability of a principle of additivity of their diamagnetic susceptibilities.
- Baliah, V.,Jeyanthy, J. Judith Diana
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p. 472 - 476
(2007/10/02)
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