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1.
Islam H. El‐Azab 《Journal of heterocyclic chemistry》2013,50(Z1):E178-E188
Preparation of 4‐chloro‐3H‐benzo[b][1,4]diazepine‐2‐carbaldehyde 5 , which is used as a key intermediate in the synthesis of chalcones derivatives, via its condensation with some aromatic acetophenone derivatives under ethanol piperidine condition was described. Also illustrated was the reaction of such chalcones with available nucleophilics and reagents of active methylene group to afford new series of fused and isolated pyrazoles, isoxazolines pyrimidines, pyridines, triazolo[1,5‐a]pyrimidines, benzo[1,4]oxa(thia)zepines, and pyrido[1,2‐a]benzimidazoles incorporating 4‐chloro‐3H‐benzo[b][1,4]diazepine moiety, which have a potential pharmaceutical interest. Furthermore, condensation reaction of 4‐chloro‐3H‐benzo[b][1,4]diazepine‐2‐carbaldehyde with aromatic amine derivatives to afford the Schiff's bases was described. The C═N double bond of the latter compounds has been reacted with chloroketene to give β‐lactams and with sulfanylacetic acid to give the 2‐(4‐oxo‐1,3‐thiazolidinyl)‐substituted derivative. The structures of the newly prepared compounds were established by elemental analysis, IR, MS, and 1H NMR spectral analysis. 相似文献
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3.
Yukiko Hayashi Prof. Dr. Yoshihiro Matano Kayo Suda Prof. Dr. Yoshifumi Kimura Prof. Dr. Yoshihide Nakao Prof. Dr. Hiroshi Imahori 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(50):15972-15983
The first comprehensive study of the synthesis and structure–property relationships of 2,2′‐bis(benzo[b]phosphole)s and 2,2′‐benzo[b]phosphole–benzo[b]heterole hybrid π systems is reported. 2‐Bromobenzo[b]phosphole P‐oxide underwent copper‐assisted homocoupling (Ullmann coupling) and palladium‐catalyzed cross‐coupling (Stille coupling) to give new classes of benzo[b]phosphole derivatives. The benzo[b]phosphole–benzo[b]thiophene and ‐indole derivatives were further converted to P,X‐bridged terphenylenes (X=S, N) by a palladium‐catalyzed oxidative cycloaddition reaction with 4‐octyne through the Cβ? H activation. X‐ray analyses of three compounds showed that the benzo[b]phosphole‐benzo[b]heterole derivatives have coplanar π planes as a result of the effective conjugation through inter‐ring C? C bonds. The π–π* transition energies and redox potentials of the cis and trans isomers of bis(benzo[b]phosphole) P‐oxide are very close to each other, suggesting that their optical and electrochemical properties are little affected by the relative stereochemistry at the two phosphorus atoms. The optical properties of the benzo[b]phosphole–benzo[b]heterole hybrids are highly dependent on the benzo[b]heterole subunits. Steady‐state UV/Vis absorption/fluorescence spectroscopy, fluorescence lifetime measurements, and theoretical calculations of the non‐fused and acetylene‐fused benzo[b]phosphole–benzo[b]heterole π systems revealed that their emissive excited states consist of two different conformers in rapid equilibrium. 相似文献
4.
The acid catalyzed ring closure of an appropriately substituted phenyl ketoester sulfide served as the initial reaction in the synthesis of several 3,4- and 3,6-disubstituted benzo[b]thiophenes. One of these compounds, 4-methoxybenzo[b]thienyl-3-acetic acid, showed marked plant growth enhancement. 相似文献
5.
T. G. Tsintsadze T. E. Khoshtariya L. N. Kurkovskaya N. T. Mirziashvili M. I. Sikharulidze 《Chemistry of Heterocyclic Compounds》2002,38(4):472-476
We describe a novel route for synthesis of benzo[b]thiopheno[2,3-e]- and benzo[b]thiopheno[3,2-f]indoles. As the starting compounds, we used the corresponding annelated isatins obtained by the Sandmeyer reaction. We have established that reduction of the latter to the corresponding unsubstituted benzo[b]thiophenoindoles depends both on the nature of the substituent and on the reaction conditions. 相似文献
6.
Yanpeng Xing Binbin Hu Qijun Yao Prof. Dr. Ping Lu Prof. Dr. Yanguang Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(38):12788-12793
5 H‐Benzo[b]carbazoles were prepared through a tandem reaction between 2‐ethynyl‐N‐triphenylphosphoranylidene anilines and α‐diazoketones through ketenimine intermediates in moderate‐to‐good yields. By using this approach, benzo[b]benzo[5,6]indolo[3,2‐h]carbazoles, fluoreno[9,1‐ab]carbazoles, and fluoreno[9,1‐ab]fluoreno[1′,9′:5,6,7]indolo[3,2‐h]carbazoles were constructed in one pot. Moreover, the resulting products emitted light within the range 410–521 nm, with quantum yields of up to 62 %. 相似文献
7.
Activated Quinones: Regiospecific Syntheses of Substituted Dibenzo [b, d]pyran-6-ones and Benzo[b]naphtho [d]pyran-6-ones The reaction of 2-methoxycarbonyl-1, 4-benzoquinone (1) with substituted phenols leads in an acid-catalyzed, regiospecific way to substituted dibenzo [b, d]-pyran-6-ones (compounds 3 and 6 ). The cycloaddition of 1,3-butadiene to the latter yields compounds 7. Tautomerisation of 7 and oxidation gives the benzo[b]-naphtho[d]pyran-6-ones 8 and 10 , respectively. 相似文献
8.
The synthesis of benzo[b]phenanthro[1,2-d]thiphene ( 1 ), benzo[b]phenanthro[4,3-d]thiophene ( 2 ), benzo-[b]phenanthro[2,1-d]thiophene ( 3 ) and benzo[b]phenanthro[3,4-d]thiophene ( 4 ) from appropriately substituted olefines by photochemical cyclodehydrogenation is described. The photolysis of olefin 9 gave a mixture of 4 and anthra[1,2-b]benzo[d]thiophene ( 5 ). 相似文献
9.
We report an efficient entry into substituted 3‐(ω‐aminoalkyl)‐benzo[b]thiophenes that allows rapid generation of structural diversity. Alkylation of α,ω‐dihaloketones with thiophenols followed by acid‐catalysed cyclisation led to an efficient synthesis of 3‐(ω‐aminoalkyl)benzo[b]thiophenes. 2‐Carboethoxy derivatives were prepared using a directed ortho‐metallation approach. These derivatives were readily converted into the corresponding amines. 相似文献
10.
[Au]/[Pd] Multicatalytic Processes: Direct One‐Pot Access to Benzo[c]chromenes and Benzo[b]furans
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Dr. Yoshihiro Oonishi Adrián Gómez‐Suárez Dr. Anthony R. Martin Dr. Yusuke Makida Prof. Dr. Alexandra M. Z. Slawin Prof. Dr. Steven P. Nolan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13507-13510
A new synthetic protocol that combines the advantages offered by eco‐friendly solvent‐free reactions and sequential transformations is reported. This strategy offers straightforward access to benzo[c]chromenes and benzo[b]furans from commercially available starting materials. This two‐step, one‐pot strategy consists of an Au‐catalyzed hydrophenoxylation process followed by Pd‐catalyzed C?H activation or Mizoroki–Heck reactions. The selectivity of the process towards C?H activation or Mizoroki–Heck reaction can be easily tuned. 相似文献
11.
S. Prez‐Silanes J. Martínez‐Esparza A. M. Oficialdegui H. Villanueva L. Orúas A. Monge 《Journal of heterocyclic chemistry》2001,38(5):1025-1030
Previous works of our group have dealt with the synthesis of 1‐(aryl)‐3‐[4‐(aryl)piperazin‐1‐yl]propane derivatives in the search for new and efficient antidepressants with a dual mode of action: serotonin reuptake inhibition and 5‐HT1A receptor afinity [1‐4]. From these studies we concluded that the 3‐[4‐(aryl)piperazin‐1‐yl]‐1‐(benzo[b]thiophen‐3‐yl)propane derivatives led to the best results. The continuation of this research project required the preparation of some new 3‐acyl‐5‐substituted benzo[b]thiophenes with a wide variety of substituents at the 5 position, ranging from nitro to hydroxyl derivatives. To obtain these derivatives we acylated the corresponding 5‐substituted benzo[b]thiophenes when it was possible. 相似文献
12.
Shyamasankar Mandal Jeet Banerjee Sougata Maity Shital K. Chattopadhyay 《Helvetica chimica acta》2021,104(3):e2000216
A synthetic protocol involving sequential use of three atom-economic processes viz. Claisen rearrangement, ring-closing metathesis and cross metathesis has been developed to access 7-substituted benzo[b]azepine and benzo[b]oxepine derivatives starting from appropriate aniline or phenol in good overall yield. A one-pot RCM-CM protocol has also been developed for the synthesis of benzazepine and benzoxepine derivatives. 相似文献
13.
Amrah Nouri Ahmad Poursattar Marjani Jabbar Khalafy 《Journal of heterocyclic chemistry》2019,56(10):2912-2921
A new series of benzo[g]thiazolo[2,3‐b]quinazolin‐4‐ium and benzo[g]benzo[4,5]thiazolo[2,3‐b]quinazolin‐14‐ium hydroxide derivatives have been synthesized by the one‐pot, three‐component reaction of aryl glyoxal monohydrates, 2‐hydroxy‐1,4‐naphthoquinone, and 2‐aminothiazole or 2‐aminobenzothiazole in the presence of triethylamine and p‐toluenesulfonic acid as organocatalysts in H2O/acetone (2:1) at room temperature. This method offers mild reaction conditions, excellent yields, easy workup, and readily accessible starting materials and catalysts. 相似文献
14.
The attempted oxidative demethylation of a series of o-dihydroxybenzo[b]thiophene methyl ethers with cerium (IV), argentic oxide, periodale and thallate usually led to intractable mixtures. However, in one ease, use of ceric ammonium nitrate resulted in nitration of the benzo[b]-thiophene ring. In another example, treatment with aqueous periodate or thallate resulted in oxidative hydroxylation of benzo[b]thiophene. 相似文献
15.
A Straightforward Route to Potent Phenolic Chain‐Breaking Antioxidants by Acid‐Promoted Transposition of 1,4‐Benzo[b]oxathiines to Dihydrobenzo[b]thiophenes
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Dr. Caterina Viglianisi Dr. Riccardo Amorati Dr. Leonardo Di Pietro Prof. Stefano Menichetti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16639-16645
The transformation of simple phenols with limited antioxidant activity into potent chain‐breaking antioxidants was achieved by a three‐step protocol, consisting of the conversion of phenols into 1,4‐benzo[b]oxathiines followed by an unprecedented acid‐promoted transposition to o‐hydroxydihydrobenzo[b]thiophenes, or dihydrobenzo[de]thiochromenes, starting from phenols or naphthols, respectively. These derivatives, bearing a benzo‐fused heterocycle with a sulfide sulfur ortho to the phenolic OH, have a rate constant of reaction with alkylperoxyl radicals (kinh) comparable to that of α‐tocopherol. A solid rationale for the transposition mechanism as well as for the structure‐antioxidant activity relationship is presented. 相似文献
16.
Yvonnick Loidreau Carole Dubouilh‐Benard Pascal Marchand Marie‐Renée Nourrisson Muriel Duflos Catherine Buquet Cécile Corbière Thierry Besson 《Journal of heterocyclic chemistry》2013,50(5):1187-1197
A useful and rapid access to libraries of N‐arylbenzo[b]furo[3,2‐d]pyrimidin‐4‐amines ( 1 ) and their novel benzo[b]thieno[3,2‐d]pyrimidin‐4‐amine analogues ( 2 ) was investigated for the first time. Title compounds were obtained via microwave‐accelerated condensation and Dimroth rearrangement of suitable anilines with N′‐(2‐cyanaryl)‐N,N‐dimethylformimidamides obtained by reaction of benzo[b]furane and benzo[b]thiophene precursors with N,N‐dimethylformamide dimethyl acetal. This work also demonstrates that well‐controlled parameters offer comfortable use of microwave technology and are both safe and beneficial to the environment. Some products obtained in this article exhibit interesting in vitro antiproliferative effects. 相似文献
17.
Yoshinori Tominaga Milton L. Lee Raymond N. Castle 《Journal of heterocyclic chemistry》1981,18(5):967-972
All isomers of the parent anthra[b]thiophenes and benzo[b]naphtho[d]thiophenes, namely anthra[2,3-b]thio-phene, anthra[2,1-b]thiophene, anthra[1,2-b]thiophene, benzo[b]naphtho[2,3-d]thiophene, benzo[b]naphtho[2,1-d]thiophene and benzo[b]naphtho[1,2-d]thiophene were synthesized using a new procedure. 相似文献
18.
Marvin L. Tedjamulia Yoshinori Tominaga Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1983,20(4):861-866
The synthesis of benzo[b]phenanthro[2, 3-d]thiophene ( 5 ), benzo[b]phenanthro[4, 3-d]thiophene ( 6 ), benzo-[b]phenanthro[2, 1-d]thiophene ( 9 ), benzo[b]phenanthro[3, 2-d]thiophene ( 14a ), anthra[1, 2-b]benzo[d]thiophene ( 24 ), anthra[2, 3-b]benzo[d]thiophene ( 29 ) and anthra[2, 1-b]benzo[d]thiophene ( 30 ) is described as well as the preparation of 13-methylbenzo[b]phenanthro[3, 2-d]thiophene ( 14b ). 相似文献
19.
A Highly Modular One‐Pot Multicomponent Approach to Functionalized Benzo[b]phosphole Derivatives
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Bin Wu Dr. Mithun Santra Prof. Naohiko Yoshikai 《Angewandte Chemie (International ed. in English)》2014,53(29):7543-7546
Benzo[b]phosphole derivatives have attracted significant attention for their unique optoelectronic properties with potential for application in materials science. Herein we report a modular approach to a benzo[b]phosphole derivative based on a one‐pot sequential coupling of an arylzinc reagent, an alkyne, dichlorophenylphosphine (or phosphorus trichloride and a Grignard reagent), and an oxidant (for example H2O2, S, or Se). The approach allows for the construction of a library of previously inaccessible, structurally diverse benzo[b]phosphole derivatives with unprecedented ease. 相似文献
20.
A variety of eleclrophilic substitution reactions have been carried out on 4-methoxybenzo[b]-thiophene (IIIa) and 4-benzoyloxybenzo[b ] thiophene (IVa). Substitution occurs in the 7-position of IIIa and, with the exception of bromination, in the 7-position of IVa. Bromination of IVa occurs in the 3-position. Bromination of 4-hydroxybenzo[b] thiophene (IIa) occurs in the 5-position. The nmr spectra of eleven disubstituted benzo[b] thiophenes have been tabulated. 相似文献