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1.
A simple,efficient,and environment benign route was developed for the preparation of bis-(indolyl)methanes and 14-aryl-14H-dibenzo[a,j]xanthenes from condensation of various aromatic aldehydes or ketones with indole,and 2-naphthol,respectively,using oxalic acid catalyst in aqueous medium.Use of cheap and easily available catalyst,better yields and simple reaction protocol are the advantages of the present method. 相似文献
2.
Oxalic acid as a catalyst for efficient synthesis of bis-(indolyl)methanes,and 14-aryl- 14H-dibenzo[a,j]xanthenes in water 总被引:1,自引:1,他引:0
A simple, efficient, and environment benign route was developed for the preparation of bis-(indolyl)methanes and 14-aryl-14H- dibenzo[aj]xanthenes from condensation of various aromatic aldehydes or ketones with indole, and 2-naphthol, respectively, using oxalic acid catalyst in aqueous medium. Use of cheap and easily available catalyst, better yields and simple reaction protocol are the advantages of the present method. 相似文献
3.
14-Aryl or alkyl-14H-dibenzo[a,j]xanthenes were prepared by condensation of 2-naphthol and aldehydes in the presence of Mg(HSO4)2 as an efficient,cheap,readily available and eco-friendly catalyst.This procedure has the advantages of high yields,easy work-up,short reaction times,and green conditions. 相似文献
4.
Xue ZL Mack J Lu H Zhang L You XZ Kuzuhara D Stillman M Yamada H Yamauchi S Kobayashi N Shen Z 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(16):4396-4407
The synthesis of [14]triphyrin(2.1.1) compounds is described. In contrast with conventional subporphyrins, which consistently contain a central boron atom, free-base heteroaromatic compounds can be formed. A modified Lindsey method was used to prepare a range of different [14]triphyrins(2.1.1) in yields of up to 35% based on the reaction of diethylpyrrole (1a) and fused pyrroles of bicyclo[2.2.2]octadiene (BCOD) (2a-e) and dihydroethanonaphthalene (4a) with various aryl aldehydes. The concentration of BF(3)·OEt(2) catalyst plays the key role in determining the yield of the [14]triphyrin(2.1.1) macrocycle relative to the conventional tetrapyrrole porphyrin product. Retro-Diels-Alder reactions of 2a-e and 4a result in the formation of [14]tribenzotriphyrin (2.1.1) (3a-e) and [14]trinaphthotriphyrin(2.1.1) (5a). The effects of exocyclic ring annulation on the electronic structure are examined in detail based on optical spectroscopy, theoretical calculations, and electrochemical measurements. The availability of free-base compounds enables the formation of [Re(I)(CO)(3)(triphyrin)] (6a) and [Ru(II)(CO)(2)Cl(triphyrin)] (7a) complexes based on a modified retro-Diels-Alder reaction. X-ray structures are reported for 4a and 6a. 相似文献
5.
Fe(HSO4)3 has been used as an efficient and reeyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14H-dibenzo[a,j]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields. 相似文献
6.
A rapid and efficient procedure for the preparation of various aryl-14H-dibenzo[a,j]xanthenes was reported.The method developed produced excellent yields via one-pot condensation of β-naphthol with various aryl-aldehydes in the presence of Keggin vanadium substituted heteropolyacid,H5PW10V2O40,as catalyst under solvent free conditions.The present methodology therefore offered several advantages but not limited to excellent yields(82%-98%),short reaction times(30-50 min),mild reaction conditions,simple work-up,as well as the utilization of cheap and environmentally benign catalyst in the absence of organic solvents. 相似文献
7.
A simple and efficient procedure for the preparation of aryl-14-H-dibenzo[a,j]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes,in the presence of silica supported sodium hydrogen sulfate(NaHSO_4/SiO_2)as a catalyst and in the absence of solvent has been developed.The present method offers several advantages such as excellent yields,short reaction time (10-30 min),mild condition,simple work-up,and the use of a cheap and environmentally friendly catalyst with remarkable reusability. 相似文献
8.
Farhad Shirini Manouchehr Mamaghani Seyyed Vahid Atghia 《Journal of the Iranian Chemical Society》2013,10(3):415-420
Nanoporous Na+-montmorillonite sulfonic acid was found to be an efficient and green catalyst for the synthesis of various 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-dodecahydroxanthene derivatives by the reaction of aldehydes with 2-naphthol and 1,3-cyclohexanedione, respectively. This novel synthetic method has the advantages of high yields, short reaction times and recyclability of the catalyst, simplicity and easy workup compared to the conventional methods reported in the literature. 相似文献
9.
A simple and efficient catalytic protocol for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes via the one-pot condensation ofβ-naphthol and aryl aldehydes using silicotungstic acid(H4[SiW12O40]) is reported.The present method offers several advantages such as high to excellent yields,short reaction times,recovery and reusability of catalyst,mild reaction conditions and easy workup procedures. 相似文献
10.
11.
WANG Hong-Mei LI Li-Cun SUN Bai-Wang LAIO Dai-Zheng JIANG Zong-Hui YAN Shi-Ping WANG Geng-Lin 《结构化学》1998,(4)
1INTRoDUCTIONMacrocycliccoordinationcomPOundshavebeenwidelyinvestigatedinthepastdecadesbecauseoftheirrelationshiptocomplexesofbiologicalsignificancesuchasthePorphyrinsandcorrins(lJ.Structuresofmanymacrocycliccompoundshavebeenre-ported,especiallythecompoundscontainingN4macrocyclicligands"'.However,toourknowledge,onlyafewcrystalstructuresofcomplexbimetallicsaltscontainingmacrocyclicligandshavebeendeterminedbyX-raydiffractionmethod.Inthispa-per,werePortthesynthesisandstructureofthetit1ecom… 相似文献
12.
Uppalaiah Kusampally Ramakanth Pagadala Chinna Rajanna Kamatala 《Tetrahedron letters》2017,58(33):3316-3318
A green, competent one-pot synthesis of 14-aryl 14H-dibenzo [a,j] xanthene and its bio-computational studies are reported. Target compounds are prepared by the condensation of 2-naphthol with benzaldehyde and its substituents using metal free benzyltrimethylammonium tribromide (BTMA-Br3) catalyst under solvent free thermal and microwave conditions. This technique has more advantages such as high yield, a clean procedure, low reaction time, simple workup and mild Lewis organo acid catalyst. 相似文献
13.
Reddi Mohan Naidu K Satheesh Krishna B Anil Kumar M Arulselvan P Ibrahim Khalivulla S Lasekan O 《Molecules (Basel, Switzerland)》2012,17(6):7543-7555
Polyethyleneglycol bound sulfonic acid (PEG-OSO?H), a chlorosulphonic acid-modified polyethylene glycol was successfully used as an efficient and eco-friendly polymeric catalyst in the synthesis of 14-aryl/heteroaryl-14H-dibenzo[a,j]xanthenes obtained from the reaction of 2-naphthol and carbonyl compounds under solvent-free conditions with short reaction times and excellent yields. The biological properties of these synthesized title compounds revealed that compounds 3b, 3c, 3f and 3i showed highly significant anti-viral activity against tobacco mosaic virus. 相似文献
14.
Benzyl-14C-1-[bis(4-fluorophenyl)methyl]-4-(2,3,4-trimethoxybenzyl) piperazine dihydrochloride (14C-KB-2796), a new cerebral vasodilator, was synthesized in order to investigate the metabolic fate. The synthesis of carboxy-14C-2,3,4-trimethoxybenzoic acid (IV) was accomplished by the reaction of 2,3,4-trimethoxybromobenzene (II) with ter-butyllithium followed by carboxylation with 14C-carbon dioxide generated from 14C-barium carbonate. Formyl-14C-2,3,4-trimethoxybenzaldehyde (VI) was prepared by the reduction of the methyl ester of IV. The free base of 14C-KB-2796 was obtained by the condensation of VI with bis(4-fluorophenyl)methyl-piperazine, and converted to I. An overall radiochemical yield from 14C-barium carbonate was 39%, the specific activity was 1,816.7 MBq/mmol (49.1 mCi/mmol) and its radiochemical purity was 99% in reverse isotope dilution analysis and thin layer chromatographic method. 相似文献
15.
Efficient method for direct preparation of 14‐aryl‐14‐H‐dibenzo[a,j]xanthenes through condensation of β‐naphthol with various aromatic aldehydes in the presence of the catalytic amount of [H—NMP]+[HSO4]? under microwave irradiation was described. This method has the advantages such as; very easy reaction workup, absolute separation of catalyst from the reaction mixture and smooth recyclability of catalyst. In this reaction 14‐aryl‐14‐H‐dibenzo[a,j]xanthenes were obtained as desired products in excellent yields and short reaction times via green and one‐pot procedure. 相似文献
16.
Biswanath Das D. Nandan Kumar Keetha Laxminarayana B. Ravikanth 《Helvetica chimica acta》2007,90(7):1330-1334
The synthesis of 14‐aryl‐ or 14‐alkyl‐14H‐dibenzo[a,j]xanthenes 3 involving the treatment of naphthalen‐2‐ol ( 1 ) with arenecarboxaldehydes or alkanals 2 in the presence of HClO4?SiO2 as a heterogeneous catalyst was achieved (Table 1), and this reaction was extended to the preparation of N‐[(2‐hydroxynaphthalen‐1‐yl)methyl]amides 5 by a three‐component reaction with urea ( 4a ) or an amide 4b – d as a third reactant (Table 2). 相似文献
17.
Yang Cao Changsheng Yao Bingbin Qin Honghong Zhang 《Research on Chemical Intermediates》2013,39(7):3055-3062
A solvent-free and efficient synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes through the one-pot condensation of β-naphthol and aldehydes catalyzed by recyclable and reusable Iron(III) triflate was reported. Notably, the presented method features short reaction time, excellent yield, and simple experimental procedure. 相似文献
18.
The synthesis of [14][14]metaparacyclophane, the first [m][n]metaparacyclophane ever known, is described. The reaction sequence began with the bis-chloromethylation of [14]paracyclophane in refluxing CS(2), which yielded a nonseparable mixture of 16,19- and 16,20-bis(chloromethyl)[14]paracyclophane in an 8:1 ratio. Acetolysis of these dichlorides gave the corresponding diacetate mixture from which the minor component 16,20-bis(acetoxymethyl)[14]paracyclophane was isolated and elaborated into the desired cyclophane via the disulfone of 2,15-dithia[16][14]metaparacyclophane and subsequent sulfur dioxide extrusion by a one-flask Ramberg-B?cklund reaction procedure followed by hydrogenation. 相似文献
19.
《Green Chemistry Letters and Reviews》2013,6(3):433-437
Abstract A simple and efficient procedure has been developed for the preparation of aryl-14H-dibenzo[a,j]xanthenes by a one-pot condensation of 2-naphthol and aryl aldehydes, in the presence of mesoporous zirconia modified with tungstophosphoric acid (ZrTPA60BT100), to be used as a heterogeneous catalyst in a solvent-free medium using conventional heating. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, and high yield. The reaction work-up is very simple and the catalyst can be easily separated from the reaction mixture and reused several times in subsequent reactions without appreciable loss of the catalytic activity. 相似文献
20.
Larry E. Overman 《Angewandte Chemie (International ed. in English)》1984,23(8):579-586
Mercury(II) and palladium(II) salts have found broad applications as catalysts for [3,3]-sigmatropic rearrangements leading to formation of C? O, C? N, C? S, and C? C σ bonds. Increases in reaction rate are often very large (1010 – 1014 at 1 M catalyst concentration) and allow many previously difficult transformations to be conducted at or near room temperature, often with attendant increases in stereoselectivity and decreases in by-product formation. The mechanism of these catalyzed transformations is briefly discussed, and evidence is summarized to suggest that many follow a cyclization-induced rearrangement mechanism. 相似文献