- Rapid and convenient thermal or microwave-assisted synthesis of substituted 2-phenylbenzothiazoles
-
A simple one-step method for the synthesis of biologically relevant 2-phenylbenzothiazoles has been developed, using sodium metabisulfite as an oxidant following condensation between 2-aminothiophenol and substituted benzaldehydes. Attractive features of
- Weekes, Ashley A.,Dix, Matthew C.,Bagley, Mark C.,Westwell, Andrew D.
-
-
Read Online
- Alumina as a support and catalyst for the synthesis of benzothiazoles in solvent-free condition
-
Arylbenzothiazole (4) and benzothiazolylcoumarins (5) were prepared by the condensation of 2-aminothiophenol (1) and hydroxybenzaldehydes (2) and 3-ethoxycarbonylcoumarinnin (3), respectively, in solvent- free condition. Of the solid support used,γ-Al2O3 demonstrated the best activity. Alinear regression line obtained from correlation between relative formation rate and Hammett constants with slope of 0.653 suggested that this condensation process is less sensitive to the substituents on the phenyl ring due to low efficacy of polarization in the solid state. In general, good yields (>80% yield) were obtained for the formation of 4. Conversely, yields of 5 were poor, because of γ-Al2O3 catalytic decomposition of 3 to form 2 (without P2O5) and coumarin (with P2O5).
- Ding, Mei-Fang,Chen, Chia-Pei,Lin, Shaw-Tao
-
-
Read Online
- Antidiabetic potential and enzyme kinetics of benzothiazole derivatives and their non-bonded interactions with α-glucosidase and α-amylase
-
Benzothiazole derivatives were synthesized and their antidiabetic potential evaluated using α-glucosidase, α-amylase, non-enzymatic glycosylation of hemoglobin and advanced glycation end product inhibition assays. Compound 3l showed low IC50 va
- Puranik, Ninad V.,Puntambekar, Hemalata M.,Srivastava, Pratibha
-
-
Read Online
- An efficient and green synthesis of 2-arylbenzothiazoles in an ionic liquid, [pmIm]Br under microwave irradiation
-
An efficient and green procedure for the synthesis of 2-arylbenzothiazoles has been developed by a simple condensation of 2-aminothiophenol and aromatic aldehyde in an inexpensive ionic liquid, 1-pentyl-3-methylimidazolium bromide ([pmIm]-Br) by microwave irradiation under solvent and catalyst-free condition. The ionic liquid is recycled for subsequent reactions.
- Ranu, Brindaban C.,Jana, Ranjan,Dey, Suvendu S.
-
-
Read Online
- An efficient copper(II)-catalyzed synthesis of benzothiazoles through intramolecular coupling-cyclization of N-(2-chlorophenyl)benzothioamides
-
A wide range of 2-aryl or 2-alkyl-substituted benzothiazoles are synthesized through intramolecular C(aryl)-S bond forming-cyclization using copper(II)-BINAM-catalyzed coupling of less reactive N-(2-chlorophenyl) benzo or alkylthioamide under mild reaction conditions (82 °C).
- Jaseer,Prasad,Dandapat, Arpan,Sekar, Govindasamy
-
-
Read Online
- Elemental sulfur mediated cyclization via redox strategy: Synthesis of benzothiazoles from o-chloronitrobenzenes and benzyl chlorides
-
A novel metal-free synthesis of 2-substituted benzothiazoles from easily available o-chloronitrobenzenes and benzyl chlorides using elemental sulfur as traceless oxidizing agent has been developed. The protocol provides a simple, efficient, and atom-economic way to access to benzothiazoles in moderate to excellent yields. And the approach exhibited good functional group tolerance.
- Wang, Xin,Miao, Dazhuang,Li, Xiaotong,Hu, Renhe,Yang, Zhao,Gu, Ren,Han, Shiqing
-
-
Read Online
- Synthesis and electronic absorption and fluorescence of 2-arylbenzothiazole derivatives
-
A series of new 2-arylbenzothiazoles have been prepared in high yields by Jacobson's cyclization condensation of 2-aminobenzenethiol with benzoyl chloride or benzaldehyde derivatives under three different routes. These compounds have been fully characterized by EA, IR, NMR and MS. The electronic absorption and fluorescence of these compounds have been systematically investigated for the first time. The relationships between their photophysical properties and structures have been discussed. The alteration of absorption and emission wavelengths can be elucidated by Hammett's substituent constants.
- Chen, Lianqing,Yang, Chuluo,Li, Suyue,Qin, Jingui
-
-
Read Online
- Metal-free aerobic oxidative C-N bond cleavage of tertiary amines for the synthesis of N-heterocycles with high atom efficiency
-
An efficient metal-free aerobic oxidative C-N bond cleavage of tertiary amines has been developed to construct N-heterocycles using molecular oxygen as the sole oxidant with high atom efficiency, in which all of the three alkyl groups in tertiary amines can be utilized and transformed into N-heterocycles. This journal is the Partner Organisations 2014.
- Chen, Xiuling,Chen, Tieqiao,Zhou, Yongbo,Han, Daoqing,Han, Li-Biao,Yin, Shuang-Feng
-
-
Read Online
- Copper containing nanosilica thioalated dendritic material: A recyclable catalyst for synthesis of benzimidazoles and benzothiazoles
-
In this paper, the design and characterization of a new heterogeneous catalyst by incorporation of copper ions into the nanosilica modified by thiole–based dendrimer are reported. The prepared catalyst was characterized by FT–IR, TGA, elemental analysis,
- Zakeri, Maryam,Moghadam, Majid,Mirkhani, Valiollah,Tangestaninejad, Shahram,Mohammadpoor-Baltork, Iraj,Pahlevanneshan, Zari
-
-
Read Online
- Iron catalyzed efficient synthesis of 2-arylbenzothiazoles from benzothiazole and olefins using environmentally benign molecular oxygen as oxidant
-
A novel protocol for iron catalyzed arylation of benzothiazole with olefins has been developed using molecular oxygen as a greener oxidant. The reaction worked smoothly using inexpensive and easily available iron as a catalyst for the synthesis of 2-arylbenzothiazole derivatives in good to excellent yields.
- Khemnar, Ashok B.,Bhanage, Bhalchandra M.
-
-
Read Online
- Synthesis and characterization of Cu(II) containing nanosilica triazine dendrimer: A recyclable nanocomposite material for the synthesis of benzimidazoles, benzothiazoles, bis-benzimidazoles and bis-benzothiazoles
-
The present study describes the synthesis, characterization, and catalytic activity of Cu(II) containing nanosilica triazine dendrimer (Cu(II)-TD@nSiO 2). The prepared catalyst was characterized by FT-IR, TGA, elemental analysis, UV-vis, FE-SEM
- Nasr-Esfahani, Mahboobeh,Mohammadpoor-Baltork, Iraj,Khosropour, Ahmad Reza,Moghadam, Majid,Mirkhani, Valiollah,Tangestaninejad, Shahram
-
-
Read Online
- N-Substituted Formamides as C1-Sources for the Synthesis of Benzimidazole and Benzothiazole Derivatives by Using Zinc Catalysts
-
An efficient and convenient one-pot protocol has been developed for the synthesis of a variety of benzimidazole, benzoxazole, and benzothiazole derivatives. This novel approach uses various o-phenylenediamines and N-substituted formamides (C1 sources) in a zinc-catalyzed cyclization in the presence of poly(methylhydrosiloxane) to afford the corresponding derivatives as sole products in moderate to excellent yields.
- Nale, Deepak B.,Bhanage, Bhalchandra M.
-
-
Read Online
- Synthesis, catalytic activity and phytotoxicity of a supported nickel(II) Schiff base complex
-
A supported Ni(II) complex has been synthesized and characterized by FTIR, UV-vis diffuse reflectance spectroscopy, thermogravimetric analysis and scanning electron microscopy. Its catalytic activity was evaluated for alkyne-azide coupling and benzothiazo
- Islam,Paul, Sumantra,Roy, Anupam Singha,Banerjee, Satabdi,Mobarok, Manir,Santra
-
-
Read Online
- Unexpectedly Simple Synthesis of Benzazoles by tBuONa-Catalyzed Direct Aerobic Oxidative Cyclocondensation of o-Thio/Hydroxy/Aminoanilines with Alcohols under Air
-
tBuONa-catalyzed direct aerobic oxidative cyclocondensation reactions of readily available alcohols and o-thio/hydroxy/aminoanilines under air have been developed and provide an efficient, practical, and green method for the synthesis of benzazoles. Mechanistic studies revealed that o-substituted anilines promote the initial aerobic alcohol-oxidation step, which explains the high reactivity and success of this unexpectedly simple and practical cyclocondensation method. Simple and straight: tBuONa-catalyzed direct aerobic oxidative cyclocondensation reactions of readily available alcohols and o-thio/hydroxy/aminoanilines under air provide an efficient, practical, and green method for the synthesis of benzazole heterocycles (see scheme). Mechanistic studies revealed that o-substituted anilines promote the initial aerobic alcohol-oxidation step.
- Shi, Xinkang,Guo, Junmei,Liu, Jianping,Ye, Mingde,Xu, Qing
-
-
Read Online
- Sulfur-Promoted Redox Cyclization of 2,2′-Dinitrodiphenyl Disulfides and Benzylamines
-
This study aims to develop green and sustainable advanced synthetic methods based on redox cyclization. Elemental sulfur is shown to promote the efficient synthesis of 2-substituted benzothiazoles from 2,2′-dinitrodiphenyl disulfides and benzylamines via redox cyclization in the absence of transition-metal catalysts and solvents. The 2-substituted benzothiazoles are obtained in good to excellent yields. This synthetic methodology is highly atom-economical and does not require any external oxidizing and/or reducing agents.
- Teramoto, Masahiro,Imoto, Mitsutaka,Takeda, Motonori,Mizuno, Takumi,Nomoto, Akihiro,Ogawa, Akiya
-
-
Read Online
- Aerobic visible-light photoredox radical C-H functionalization: Catalytic synthesis of 2-substituted benzothiazoles
-
An aerobic visible-light driven photoredox catalytic formation of 2-substituted benzothiazoles through radical cyclization of thioanilides has been accomplished. The reaction features C-H functionalization and C-S bond formation with no direct metal involvement except the sensitizer. The reaction highlights the following: (1) visible-light is the reaction driving force; (2) molecular oxygen is the terminal oxidant, and (3) water is the only byproduct.
- Cheng, Yannan,Yang, Jun,Qu, Yue,Li, Pixu
-
-
Read Online
- Formation of a nanorod shaped ionogel and its high catalytic activity for one-pot synthesis of benzothiazoles
-
An ionogel was synthesized through the confinement of 1,3,5-trimethyl pyrazolium chloride as an ionic liquid in a silica-gel matrix through a sol-gel process, and its catalytic activity was compared with a silica supported ionic liquid for the synthesis of benzothiazoles using 2-aminothiophenol and aldehydes/ketones. The reaction between 3-methoxyacetophenone and 2-aminothiophenol produced 2-(3-methoxyphenyl)benzothiazole, and its structure was determined using X-ray crystallography. The ionogel was characterized with SEM, TEM, FTIR and TGA.
- Sharma, Pankaj,Gupta, Monika,Kant, Rajni,Gupta, Vivek K.
-
-
Read Online
- Elemental Sulfur-Mediated Decarboxylative Redox Cyclization Reaction: Copper-Catalyzed Synthesis of 2-Substituted Benzothiazoles
-
A S 8 -mediated directed decarboxylative redox-cyclization strategy for the synthesis of 2-substituted benzothiazoles from o -iodoanilines, arylacetic acids, and elemental sulfur catalyzed by cheap copper metal has been developed. This reaction is operationally simple, ligand-free, compatible with a wide range of functional groups, and provides the desired products in good to excellent yields. In addition, a gram-scale experiment was carried out to furnish PMX 610, an antitumor drug.
- Wang, Xin,Li, Xiaotong,Hu, Renhe,Yang, Zhao,Gu, Ren,Ding, Sai,Li, Pengyi,Han, Shiqing
-
-
Read Online
- One-pot synthesis of 2-aryl-and 2-alkylbenzo-thiazoles under microwave irradiation
-
Eco-friendly direct solvent-free reactions of o-aminothiophenol and aromatic or aliphatic β-keto esters with microwave irradiation produced 2-substituted benzothiazoles in excellent yield. Experiments that compared microwave irradiation to conventional heating methods showed that the former gives the 2-substituted benzothiazoles faster and in higher yields. The formation of the titled compounds probably involves the nucleophilic addition of the thiol group to the keto group of the β-keto ester with subsequent elimination of ethyl acetate from the resulting adduct. The adduct then undergoes an intramolecular addition of the o-amino group to the carbonyl group to give an adduct from which water is eliminated to afford the 2- substituted benzothiazoles.
- Kamila, Sukanta,Zhang, Hongming,Biehl, Edward R.
-
-
Read Online
- Synthesis, characterization, and applications of novel Co(II)-pyridoxal phosphate-Schiff base/SBA-15 as a nanocatalyst for the green synthesis of benzothiazole heterocycles
-
Mesoporous heterogeneous santa barbara amorphous (SBA)-15-supported cobalt complex, as a novel nanocatalyst containing N–O chelating Schiff-base ligand was successfully synthesized by the reaction of SBA-15 and Cobalt(II)-Schiff-base complex. The Co(II)-S
- Yari, Hassan,Dehkharghani, Rahebeh A.,Bardajee, Ghasem R.,Akbarzadeh-T, Niloufar
-
-
Read Online
- Photoinduced Heterogeneous C?H Arylation by a Reusable Hybrid Copper Catalyst
-
Heterogeneous copper catalysis enabled photoinduced C?H arylations under exceedingly mild conditions at room temperature. The versatile hybrid copper catalyst provided step-economical access to arylated heteroarenes, terpenes and alkaloid natural products with various aryl halides. The hybrid copper catalyst could be reused without significant loss of catalytic efficacy. Detailed studies in terms of TEM, HRTEM and XPS analysis of the hybrid copper catalyst, among others, supported its outstanding stability and reusability.
- Choi, Isaac,Müller, Valentin,Lole, Gaurav,K?hler, Robert,Karius, Volker,Vi?l, Wolfgang,Jooss, Christian,Ackermann, Lutz
-
-
Read Online
- One-pot copper-catalyzed synthesis of 2-substituted benzothiazoles from 2-iodoanilines, benzyl chlorides and elemental sulfur
-
An efficient one-pot three-component reaction of 2-iodoanilines, benzyl chlorides and elemental sulfur to form 2-substituted benzothiazoles in satisfactory yields (up to 98%) has been described. The reaction tolerated a wide range of functional groups on the aromatic ring. And heterocycle methylene chlorides substrates were also found to be compatible.
- Yang, Zhao,Hu, Renhe,Li, Xiaotong,Wang, Xin,Gu, Ren,Han, Shiqing
-
-
Read Online
- S8-Mediated Cyclization of 2-Aminophenols/thiophenols with Arylmethyl Chloride: Approach to Benzoxazoles and Benzothiazoles
-
A metal-free approach to benzazoles from arylmethyl chlorides and 2-mercaptan/2-hydroxyanilines using elemental sulfur as a traceless oxidizing agent has been developed. The reactions proceeded in good to excellent yields, exhibiting good functional groups tolerance and gram-scale ability. A key mechanistic investigation indicated that the key intermediate trisulfide 6, which was characterized by NMR, HRMS and crystal X-ray crystallography, was separated in the reaction prior to the formation of the product.
- Gan, Haifeng,Miao, Dazhuang,Pan, Qiang,Hu, Renhe,Li, Xiaotong,Han, Shiqing
-
-
Read Online
- Synthesis of 2-Arylbenzothiazoles by Copper-Catalyzed One-Pot Three-Component Reactions in Water
-
Copper-catalyzed three-component reactions of 2-iodoanilines, benzylamines, and sulfur powder are reported to afford benzothiazoles in a simple one-pot procedure by using water as solvent. A variety of 2-arylbenzothiazoles were obtained in moderate to good yields up to 88%.
- Xu, Hualong,Luo, Chun,Li, Zhengkai,Xiang, Haifeng,Zhou, Xiangge
-
-
Read Online
- Palladium(0) nanoparticles-catalyzed ligand-free direct arylation of benzothiazole via C-H bond functionalization
-
Palladium nanoparticles, generated in situ efficiently catalyzes direct 2-C-H arylation of benzothiazole without requirement of any ligand. A wide range of substituted aryl and heteroaryl iodides participate in this reaction producing a series of 2-aryl/heteroaryl-benzothiazoles in high yields.
- Saha, Debasree,Adak, Laksmikanta,Ranu, Brindaban C.
-
-
Read Online
- One-pot tandem approach for the synthesis of benzothiazoles from benzyl halides
-
A one-pot tandem approach for the synthesis of benzothiazoles from benzyl halides and o-aminobenzenethiol was described. Benzothiazoles were obtained in high chemical yields under mild conditions in DMSO in the absence of an additional oxidant. Both benzy
- Zhu, Chen,Akiyama, Takahiko
-
-
Read Online
- Probing the Effects of the Number and Positions of ?OCH3 and ?CN Substituents on Color Tuning of Ir(III) Complex Derivatives through a Joint Computational and Experimental Study
-
We performed a joint theoretical and experimental study on sixteen Ir(III) complexes bearing a similar molecular platform of bis(2-phenylbenzothiozolato-N,C2’) iridium(III) (acetylacetonate) by grafting ?OCH3 group and/or ?CN group on different positions of the C-related arene moiety of the (Formula presented.) ligand (C-ring). Our results reveal that the introduction of ?CN renders an overall drop in the FMO energy levels while a reverse increase is observed for ?OCH3. The ortho- and para-sites of the C-ring are more effective substitution positions to modulate the HOMO energy level due to the fact that the electronic density of HOMO mainly locates at them while the meta-site would induce a stronger impact on LUMO since the electronic density of LUMO mainly distributes over the position. Utilizing the synergistic effects of the substituents and the substituted positions, a wide color-tuning range from 479 nm to 637 nm was achieved, which covers nearly the whole window of visible spectrum. In particular, the tri-substituted Ir35mo4cn complex (λem max=637 nm) may be a potential candidate for high efficiency red OLEDs materials due to its greatly enhanced absorption processes, relatively higher 3MLCT (%), lower ΔES1–T1, enlarged separation between 3MLCT/π–π* and 3MC d–d states, and good hole and particle-transporting performances. Finally, six representative complexes were synthesized and their spectra were determined, which confirm the reliability of our computational strategy.
- Jiao, Yan,Li, Ming,Lu, Zhiyun,Luo, Yi,Pu, Xumei,Qin, Xiao,Wang, Ning,Xiang, Minghui,Yuan, Rongao
-
-
Read Online
- Cuprous cluster as effective single-molecule metallaphotocatalyst in white light-driven C[sbnd]H arylation
-
This study investigated a series of ferrocenyltelluroether based cuprous halide clusters as effective single-molecule metallaphotocatalysts (SMP) in white light-driven C[sbnd]H arylation at room temperature and air. A systematic mechanistic study reveals that Cu(I) cluster can be irradiated by visible light to promote proton-coupled electron transfer (PCET), during which the electron from Cu(I)* leaves together with the proton from benzothiazole C[sbnd]H, leading to the formation of benzothiazolate-coordinated Cu(II) intermediate and aryl radical. Subsequently, the electron transfer (ET) from the ferrocene unit to the Cu(II) center releases the reactive benzothiazolate to form the target product with aryl radical. The advantages of these copper(I) halide clusters as SMP include high photocatalytic efficiency, structure adjustability, mild reaction conditions and good functional group tolerance.
- Ji, Wei,Wang, Hao,Li, Cheng-An,Gao, Fei,An, Zhong-Fu,Huang, Ling,Wang, He,Pan, Yue,Zhu, Dun-Ru,Wang, Jian-Qiang,Guo, Cheng,Mayoral, José A.,Jing, Su
-
-
Read Online
- Color tunable phosphorescent light-emitting diodes based on iridium complexes with substituted 2-phenylbenzothiozoles as the cyclometalated ligands
-
Several iridium complexes {iridium(III)bis[2-(3-methoxyphenyl)-1,3- benzothiozolato-N,C2′] acetylacetonate (MeO-BT) 2Ir(acac), iridium(III)bis[2-(2,4-difluorophenyl)-1,3- benzothiozolato-N,C2′] acetylacetonate (2F-BT) 2Ir(acac), and iridium(III)bis[2-(2,4-difluorophenyl)-6-fluoro-1,3- benzothiozolato-N,C2′] acetylacetonate (3F-BT) 2Ir(acac)} having different substituents on 2-phenylbenzothiazole have been synthesized. Several iridium complexes {iridium(III)bis[2-(3- methoxyphenyl)-1,3-benzothiozolato-N,C2′] acetylacetonate (MeO-BT)2Ir(acac), iridium(III)bis[2-(2,4-difluorophenyl)-1,3- benzothiozolato-N,C2′] acetylacetonate (2F-BT) 2Ir(acac), and iridium(III)bis[2-(2,4-difluorophenyl)-6-fluoro-1,3- benzothiozolato-N,C2′] acetylacetonate (3F-BT) 2Ir(acac)} having different substituents on 2-phenylbenzothiazole have been synthesized. The phosphorescent light emitting diodes (PHOLEDs) using these iridium complexes as dopant emitters were fabricated. The experimental results revealed that the emissive colors of PHOLEDs could be finely tuned by suitable modification of the substituents on the 2-phenylbenzothiazole ligands. Furthermore, these iridium complexes show better emissive properties than the known iridium(III)bis(2-phenylbenzothiozolato-N,C2′) acetylacetonate (BT)2Ir(acac).
- Chang, Wei-Chieh,Hu, Andrew Teh,Duan, Jiun-Pey,Rayabarapu, Dinesh Kumar,Cheng, Chien-Hong
-
-
Read Online
- PTSA catalyzed simple and green synthesis of benzothiazole derivatives in water
-
p-Toluenesulfonic acid (10 mol%) was found to be an effective and efficient catalyst for the synthesis of 2-substituted benzothiazoles from aromatic aldehydes and 2-aminothiophenol in moderate to excellent yields in water. This method provides a simple an
- Azizi, Najmedin,Amiri, Alireza Khajeh,Baghi, Roya,Bolourtchian, Mohammad,Hashemi, Mohammad M.
-
-
Read Online
- Elemental sulfur disproportionation in the redox condensation reaction between o-halonitrobenzenes and benzylamines
-
The disproportionation of elemental sulfur at moderate temperatures is investigated in the redox condensation involving o-halonitrobenzenes 1 and benzylamines 2. As a redox moderator, elemental sulfur plays the dual role of both electron donor and acceptor, generating its lowest and highest oxidation states: S-2 (sulfide equivalent) in benzothiazole 3 and S+6 (sulfate equivalent) in sulfamate 4, and filling the electron gap of the global redox condensation process. Along with this process, a cascade of reactions of reduction of the nitro group of 1, oxidation of the aminomethyl group of 2, metal-free aromatic halogen substitution, and condensation finally led to 2-arylbenzothiazoles 3.
- Nguyen, Thanh Binh,Ermolenko, Ludmila,Retailleau, Pascal,Al-Mourabit, Ali
-
-
Read Online
- Synthesis of 2-aryl-benzothiazoles via Ni-catalyzed coupling of benzothiazoles and aryl sulfamates
-
2-Aryl-benzothiazoles have been successfully synthesized via a simple coupling reaction between benzothiazoles and aryl sulfamates using a nickel catalyst. The nickel catalyst is inexpensive, reusable and commercially available. In addition, the use of highly expensive palladium catalysts and unstable raw materials has been avoided. 2-Aryl-benzothiazoles bearing various substituents on the aryl groups were obtained in good yield.
- Gou, Liping,Song, Renyuan,Wang, Guangrong,Yu, Xiaofeng,Zhang, Zhen
-
-
Read Online
- Formation of amides, their intramolecular reactions for the synthesis of N-heterocycles, and preparation of a marketed drug, sildenafil: A comprehensive coverage
-
A unified approach to the tandem preparation of diverse nitrogen heterocycles via decarboxylative acylation of ortho-substituted amines with α-oxocarboxylic acids and subsequent intramolecular cyclizations has been developed. The key features of this work include: the first example of transition-metal-free decarboxylative amidation of α-oxocarboxylic acids with ortho-substituted amines, realization of intramolecular cyclization of amides employing nucleophiles that have previously been unexplored, mechanistic investigation of an unprecedented K2S2O8 promoted amide formation and its subsequent intramolecular cyclizations, and application to the synthesis of a best-selling marketed drug.
- Laha, Joydev K.,Patel, Ketul V.,Satyanarayana Tummalapalli,Dayal, Neetu
-
-
Read Online
- Atom economic palladium catalyzed novel approach for arylation of benzothiazole and benzoxazole with triarylbismuth reagents via C[sbnd]H activation
-
We have developed a novel method for the direct C[sbnd]H functionalization of benzothiazole and benzoxazole using triarylbismuth reagents. The arylation proceeds using the homogeneous catalytic system PdCl2, Cu(OAc)2 and PPh3 ligand. Triarylbismuthines, which act as threefold arylating reagents, have low toxicity, are green and ecofriendly. These methodologies are particularly useful to prepare arylated benzothiazoles and benzoxazoles.
- Balsane, Kishor Eknath,Gund, Sitaram Haribhau,Nagarkar, Jayashree Milind
-
-
Read Online
- Perchloric acid-doped polyaniline as an efficient and reusable catalyst for the synthesis of 2-substituted benzothiazoles
-
2-Substituted benzothiazoles have been efficiently synthesized in good yields by the condensation reaction of o-aminothiophenol with aldehydes in the presence of a catalytic amount of perchloric acid-doped polyaniline (HClO4/PANI). The low cost, simple re
- Abdollahi-Alibeik, Mohammad,Poorirani, Safoora
-
-
Read Online
- NCS/TBHP promoted C2 arylation of benzothiazoles with aldehydes in DMSO
-
A N-chlorosuccinimide catalyzed oxidative synthesis of 2-aryl benzothiazole from benzothiazoles and aryl aldehydes using tert-butyl peroxybenzoate as an oxidant in dimethyl sulfoxide (DMSO) has been developed in moderate to good yields. Solvent DMSO as a strong Lewis base plays an efficient role in the reaction. Various substrates were tolerated under optimized conditions affording the arylated products in 12–94% yields for 28 examples. Additionally, acylated benzothiazoles were produced with 4 examples.
- Xu, Wen-Xiu,Ye, Fei-Xia,Liu, Xing-Hai,Weng, Jian-Quan
-
-
Read Online
- Synthesis, characterization, crystal structures, and anticancer activity of some new 2,3-dihydro-1,5-benzoxazepines
-
Various benzoxazepine derivatives have been synthesized and characterized using IR, NMR, GC–MS, and microanalysis. The single-crystal X-ray structures of 2,2-dimethyl-4-[(E)-2-(4-methylphenyl)ethenyl]-2,3-dihydro-1,5-benzoxazepine (RS01), 4-[(E)-2-(2-chlo
- Odame, Felix,Schoeman, Recardia,Krause, Jason,Hosten, Eric C.,Tshentu, Zenixole R.,Frost, Carminita
-
-
Read Online
- Ultrafine Pt nanoparticles supported on a dendrimer containing thiol groups: An efficient catalyst for the synthesis of benzimidazoles and benzothiazoles from benzyl alcohol derivatives in water
-
A novel and unique platform was prepared based on a dendrimer containing thiol groups supported on nanosilica (nSTDP), and ultrafine platinum nanoparticles were synthesized and immobilized on the thiol decorated branches of nSTPD. The new catalyst, (Ptnp?nSTDP), was characterized by different techniques such as FE-SEM, TEM, ICP, XPS and DR UV-vis. This heterogeneous catalyst presented an outstanding performance for the synthesis of benzimidazole and benzothiazole derivatives through a reaction between benzyl alcohol derivatives and 2-aminothiophenol or 1,2-phenylenediamine. No requirement for the pre-reduction of catalysts and using water as a green solvent make it an individual catalyst for these reactions. Furthermore, the catalyst can be easily recovered and reused five consecutive times in the production of benzimidazoles and benzothiazoles without significant leaching of Pt and loss of its activity which illustrated the chemical stability of the catalyst during the reaction.
- Bahadori, Mehrnaz,Landarani-Isfahani, Amir,Mirkhani, Valiollah,Moghadam, Majid,Mohammadpoor-Baltork, Iraj,Nori, Zahra Zamani,Tangestaninejad, Shahram
-
-
Read Online
- K2S2O8activation by glucose at room temperature for the synthesis and functionalization of heterocycles in water
-
While persulfate activation at room temperature using glucose has primarily been focused on kinetic studies of the sulfate radical anion, the utilization of this protocol in organic synthesis is rarely demonstrated. We reinvestigated selected K2S2O8-mediated known organic reactions that invariably require higher temperatures and an organic solvent. A diverse, mild functionalization and synthesis of heterocycles using the inexpensive oxidant K2S2O8 in water at room temperature is reported, demonstrating the sustainability and broad scope of the method. Unlike traditional methods used for persulfate activation, the current method uses naturally abundant glucose as a K2S2O8 activator, avoiding the use of higher temperature, UV light, transition metals or bases.
- Hunjan, Mandeep Kaur,Laha, Joydev K.
-
-
Read Online
- Tuning the Excited State of Tetradentate Pd(II) and Pt(II) Complexes through Benzannulated N-Heteroaromatic Ring and Central Metal
-
A series of tetradentate Pd(II) and Pt(II) complexes containing fused 5/6/6 metallocycles with phenyl N-heteroaromatic benzo[d]imidazole (pbiz), benzo[d]oxazole (pboz) or benzo[d]thiazole (pbthz)-containing ligands was developed. Systematic studies by exp
- Fang, Xiaoli,Guo, Hua,Li, Guijie,Lou, Weiwei,She, Yuanbin,Sun, Yulu,Yang, Yun-Fang,Zhang, Qisheng
-
p. 223 - 234
(2021/12/16)
-
- Visible-Light Carbon Nitride-Catalyzed Aerobic Cyclization of Thiobenzanilides under Ambient Air Conditions
-
A metal-free heterogeneous photocatalysis has been developed for the synthesis of benzothiazoles via intramolecular C-H functionalization/C-S bond formation of thiobenzanilides by inexpensive graphitic carbon nitride (g-C3N4) under visible-light irradiation. This reaction provides access to a broad range of 2-substituted benzothiazoles in high yields under an air atmosphere at room temperature without addition of a strong base or organic oxidizing reagents. In addition, the catalyst was found to be stable and reusable after five reaction cycles.
- Bai, Jin,Yan, Sijia,Zhang, Zhuxia,Guo, Zhen,Zhou, Cong-Ying
-
supporting information
p. 4843 - 4848
(2021/06/28)
-
- Diversity in Heterocycle Synthesis Using α-Iminocarboxylic Acids: Decarboxylation Dichotomy
-
Despite the structural similarity with imines, α-iminocarboxylic acids have seldom been used in heterocycles synthesis. The reactions of ortho-substituted anilines and arylglyoxylic acids in DMSO at 40 °C gave various benzo-fused five- to six-membered N-heterocycles in good to excellent yields. The reaction proceeds via intramolecular Michael addition of α-iminocarboxylic acids, generated in situ, with an ortho-substituted nucleophile, yielding an isolable unprecedented tetrahedral carboxylic acids, which upon decarboxylation without any aid of additional reagents forms the N-heterocycles. DMSO is crucial in this reaction, perhaps because of improved solubility and the ease of decarboxylation of these tetrahedral carboxylic acids. However, a copper-catalyzed reaction of ortho-substituted anilines and 2-bromoarylglyoxylic acids gave a dibenzo-fused seven-membered N-heterocycle under a basic reaction condition. Unlike intramolecular cyclization with α-iminocarboxylic acids in the first case, α-iminocarboxylic acid undergoes a competitive decarboxylation under the copper-catalyzed conditions, which upon subsequent heteroarylation form the heterocycles. Taken together, the study described herein represents two different modes of decarboxylation observed with α-iminocarboxylic acids, leading to the synthesis of divergent heterocycles and pharmaceuticals, which remained unexplored previously.
- Hunjan, Mandeep Kaur,Laha, Joydev K.
-
-
- Photocatalyst- And Transition-Metal-Free Visible-Light-Promoted Intramolecular C(sp2)-S Formation
-
A photocatalyst- and transition-metal-free visible-light-induced cyclization of ortho-halothiobenzanilides has been developed. Upon irradiation with visible light, substrates undergo dehalogenative cyclization to 2-aryl benzothiazoles with high efficiency and selectivity. This photocyclization exhibits a high tolerance to various functional groups, is applicable for the synthesis of 2-alkyl benzothiazoles, and is easy to set up for gram-scale reaction.
- Wang, Hao,Wu, Qi,Zhang, Jian-Dong,Li, Hai-Yan,Li, Hong-Xi
-
p. 2078 - 2083
(2021/04/05)
-
- Oxidant/Solvent-Controlled I2-Catalyzed Domino Annulation for Selective Synthesis of 2-Aroylbenzothiazoles and 2-Arylbenzothiazoles under Metal-Free Conditions
-
A simple and practical domino protocol for the selective synthesis of 2-aroylbenzothiazoles and 2-aryl benzothiazoles catalyzed by I2 is developed under metal-free conditions. The reaction outcomes are exclusively controlled by the reaction oxidant/medium. With DMSO employed as both the solvent and the oxidant, an oxidation of aromatic methyl ketones takes precedence over the condensation with 2-aminobenzenethiols. On the other hand, when the reaction was carried out in PhNO2 or in 1,4-dioxane containing PhNO2, the condensation of aromatic methyl ketones with 2-aminobenzenethiols has priority to form imines which is followed by an oxidation of the methyl group from ketones to afford 2-arylbenzothiazoles as a sole product. The PhNO2/I2 co-catalytic system is proposed first time.
- Ma, Renchao,Ding, Yuxin,Chen, Rener,Wang, Zhiming,Wang, Lei,Ma, Yongmin
-
p. 310 - 321
(2021/01/09)
-
- KOtBu-Promoted Halogen-Bond-Assisted Intramolecular C-S Cross-Coupling of o-Iodothioanilides for the Synthesis of 2-Substituted Benzothiazoles
-
An efficacious and mild KOtBu-promoted intramolecular C-S cross-coupling of ortho-iodothioanilides in conjunction with a catalytic quantity of phenanthroline as an additive has been described for the convenient synthesis of 2-substituted benzothiazoles. The methodology is suitable for attaining a wide variety of 2-alkyl- and 2-aryl-substituted benzothiazoles. Single-crystal XRD, DFT calculations, NMR, and UV studies suggest that halogen bonds between the units of ortho-iodothioanilides may assist in the electron transfer process.
- Nandy, Anuradha,Sekar, Govindasamy
-
p. 15825 - 15834
(2021/11/01)
-
- Method for preparing benzothiazole compound from visible light promoted N-(2-bromophenyl) thioamide
-
The invention discloses a method for preparing a benzothiazole compound from N-(2-bromophenyl) thioamide under the promotion of visible light. Specifically, under the protection of inert gas, according to the molar ratio of N-(2-bromophenyl) thioamide to inorganic base being 1: 0.5, reactants are added into a reaction container provided with a stirring device, then dimethyl sulfoxide is added, and stirring reaction is carried out for 2-24 hours at room temperature under the irradiation of visible light to obtain the benzothiazole compound. Under the condition of not adding any photosensitizer or transition metal catalyst, sodium phosphate is used as alkali, and under the irradiation of a 45W household compact fluorescent lamp, a series of intramolecular cross-coupling reactions of N-(2-bromophenyl) thioamide are realized. In addition, the benzothiazole compound can be obtained with high yield. The whole process is green, efficient and easy to operate, and the method is a good method for synthesizing the benzothiazole compound.
- -
-
Paragraph 0085-0087
(2021/06/22)
-
- Preparation method of 2-substituted benzothiazole
-
The invention discloses a preparation method of 2-substituted benzothiazole, and belongs to the field of organic chemical synthesis. The preparation method of the 2-substituted benzothiazole specifically comprises the following steps: by taking an N-aryl thioamide compound as a raw material and taking graphite-phase carbon nitride (g-C3N4) prepared by urea thermal polymerization condensation as aphotocatalyst, carrying out a cyclization reaction under a mild condition to prepare the 2-substituted benzothiazole. The method has the advantages of simple operation, cheap and easily available catalyst, mild reaction conditions, wide substrate application range, no strong oxidant and no metal residue, and provides an economical, practical, green and environment-friendly new method for synthesisof 2-substituted benzothiazole widely applied to the fields of medicines, dyes, pesticides and the like.
- -
-
Paragraph 0094-0099
(2020/11/09)
-
- Preparation method of substituted benzothiazole C2 arylated derivative
-
The invention discloses a substituted benzothiazole C2 arylated derivative and a preparation method thereof. The preparation method comprises the following steps: mixing substituted benzothiazole represented by a formula (II) and substituted benzaldehyde represented by a formula (III); adding a free radical initiator N-chlorosuccinimide (NCS) and an oxidant tert-butyl hydroperoxide (TBHP), carrying out a stirring reaction for about 12 h at 120 DEG C in a nitrogen atmosphere by using DMSO as a solvent, and after the reaction is finished, separating and purifying the reaction liquid to prepare the substituted benzothiazole C2 arylated derivative represented by a formula (I). The invention provides a new method for synthesizing a benzothiazole C2 arylated derivative by taking an NCS/TBHP double component as an oxidation system through a stirring and reaction for about 12 hours at 120 DEG C in a nitrogen atmosphere under the assistance of a strong Lewis base DMSO; and according to the method, an NCS/TBHP double-component oxidation system and an aprotic solvent are selected, and the method has the advantages of being simple in catalytic system, good in product yield and wide in substrate range.
- -
-
Paragraph 0025-0026
(2020/05/02)
-
- Aerobic oxidative synthesis of quinazolinones and benzothiazoles in the presence of laccase/DDQ as a bioinspired cooperative catalytic system under mild conditions
-
The current study applied laccase/DDQ as a bioinspired cooperative catalytic system for the synthesis of quinazolinones (80-95% yield) and benzothiazoles (65-98% yield) using air or O2 as ideal oxidants in aqueous media at ambient temperature. The aerobic oxidative cyclization reactions occur in two steps: (i) chemical cyclization; (ii) chemoenzymatic oxidation. These methods are more environment-friendly, efficient, simple and practical than other reported methods due to the use of O2 as an oxidant, laccase as an eco-friendly biocatalyst, aqueous media as the solvent and free from any toxic transition metal and halide catalysts. Therefore, these methods can be applied in pharmaceutical and other sensitive synthetic procedures.
- Abdelrasoul, Amira,Ghorashi, Nadia,Moradi, Reza,Rostami, Amin,Shokri, Zahra
-
p. 14254 - 14261
(2020/04/23)
-
- Sulfamic acid-catalyzed conversion of o-aminothiophenol and aromatic aldehydes to 2-arylbenzothiazoles
-
Non-metallic, non-toxic, and cheap sulfamic acid was used as a catalyst for the synthesis of 2-arylbenzothiazole from o-aminothiophenol and aromatic aldehydes bearing electron-donating or electron-withdrawing groups. The sulfamic acid catalyst can be reus
- Shi, Chunjie,Song, Renyuan,Wang, Guangrong,Yu, Xiaofeng
-
p. 871 - 879
(2020/09/09)
-
- Probing the effects of the number and positions of –OCH3 and –CN substituents on color tuning of Ir(III) complex derivatives through a joint computational and experimental study
-
We performed a joint theoretical and experimental study on sixteen Ir(III) complexes bearing a similar molecular platform of bis(2-phenylbenzothiozolato-N,C2’) iridium(III) (acetylacetonate) by grafting – OCH3 group and/or – CN group on different positions of the C-related arene moiety of the C^N ligand (Cring). Our results reveal that the introduction of – CN renders an overall drop in the FMO energy levels while a reverse increase is observed for – OCH3. The ortho- and para-sites of the C-ring are more effective substitution positions to modulate the HOMO energy level due to the fact that the electronic density of HOMO mainly locates at them while the meta-site would induce a stronger impact on LUMO since the electronic density of LUMO mainly distributes over the position. Utilizing the synergistic effects of the substituents and the substituted positions, a wide color-tuning range from 479 nm to 637 nm was achieved, which covers nearly the whole window of visible spectrum. In particular, the tri-substituted Ir35mo4cn complex (λemmax=637 nm) may be a potential candidate for high efficiency red OLEDs materials due to its greatly enhanced absorption processes, relatively higher3MLCT (%), lower ΔES1–T1, enlarged separation between3MLCT/π–π* and3MC d–d states, and good hole and particle-transporting performances. Finally, six representative complexes were synthesized and their spectra were determined, which confirm the reliability of our computational strategy.
- Qin, Xiao,Li, Ming,Xiang, Minghui,Luo, Yi,Jiao, Yan,Yuan, Rongao,Wang, Ning,Lu, Zhiyun,Pu, Xumei
-
p. 470 - 481
(2019/06/03)
-
- SPIRO-CONTAINING PLATINUM (II) EMITTERS WITH TUNABLE EMISSION ENERGIES AND SYNTHESES THEREOF
-
An asymmetric tetradentate metal complex of a N^C^C^N comprising tetradentate ligand has a metal connected to binding sites which are connected to each other via three or four covalent bonds that can be either single or double bonds with bridging linkers reside between C^C and C^N moieties. These linkers result in three-dimension metal complexes with distorted square planar geometries. The four donor atoms coordinate to a metal center. Upon metal binding a 5-6-6 membered metallocycle is formed upon chelation including a first nitrogen donor bond, a first metal-carbon bond, a second metal-carbon bond, and a second nitrogen donor bond. The light emission from these metal complexes can be tuned by the ligand structure over the entire visible spectrum.
- -
-
Page/Page column 20
(2019/08/12)
-
- Method for synthesizing benzothiazole by microwave radiation of benzothioamide compound in aqueous phase
-
The invention discloses a method for synthesizing benzothiazole by microwave radiation of a benzothioamide compound in an aqueous phase. The method includes the steps: adding the benzothioamide compound into the aqueous phase under microwave conditions; performing cyclization under alkaline conditions to generate the benzothiazole. The method for preparing the benzothiazole is environmentally friendly, simple and convenient in operation, safe, cheap and efficient. Compared with the prior art, the method is applicable to a lot of functional groups, high in yield, few in by-products, simple in operation, safe, low in cost and environmentally friendly.
- -
-
Paragraph 0013; 0037
(2019/02/13)
-
- Method used for rapid preparation of benzo-heterocycle compound with physical grinding under solvent-free room temperature conditions
-
The invention discloses a method used for rapid preparation of benzo-heterocycle compound with physical grinding under solvent-free room temperature conditions. According to the method, glacial aceticacid is taken as a catalyst; at solvent-free room temperature conditions, physical grinding is adopted, reaction of 2-substituted arylamines (2-mercapto arylamine, 2-aminophenol, and o-phenylenediamine) and aromatic aldehydes is carried out using physical grinding. The method is friendly to the environment, is simple in operation, is safe, is low in cost, and is high in efficiency. Compared withthe prior art, the advantages are that: the method is suitable for a large amount of functional groups, yield is high, less by-product is generated, operation is simple, the method is safe, cost is low, and the method is friendly to the environment.
- -
-
Paragraph 0062; 0142
(2019/01/21)
-
- Metal-free synthesis of N-containing heterocycles from O-substituted aniline derivatives via 2,4,6-trihydroxybenzoic acid-catalyzed oxidative dehydrogenation of benzylamines under oxygen atmosphere
-
A series of N-heterocycles, i.e., benzimidazoles, benzoxazoles, and benzothiazoles, can be conveniently synthesized by the oxidative cyclization of benzylamines with o-substituted aniline derivatives, i.e., o-phenylenediamines, o-aminophenols, and o-aminothiophenols, using 2,4,6-trihydroxybenzoic acid as an organocatalyst under an oxygen atmosphere. This approach provides a mild and efficient tool towards benzimidazoles and benzothiazoles with good yields and a broad substrate scope. The developed synthesis of N-heterocycles might proceed via the oxidative dehydrogenation of benzylamines (ArCH2NH2), generating the corresponding imines (ArCH=NH) as key intermediates.
- Kumazawa, Shun,Uematsu, Akinori,Dong, Chun-Ping,Kodama, Shintaro,Nomoto, Akihiro,Ueshima, Michio,Ogawa, Akiya
-
p. 842 - 853
(2019/04/26)
-
- Phosphine free Mn-complex catalysed dehydrogenative C-C and C-heteroatom bond formation: A sustainable approach to synthesize quinoxaline, pyrazine, benzothiazole and quinoline derivatives
-
Herein the first sustainable synthesis of quinoxalines, pyrazines and benzothiazoles catalysed by a phosphine free Mn(i) complex via acceptorless dehydrogenative coupling (ADC) is reported. This method is also applied successfully to synthesize quinolines via the dehydrogenation (removal of H2) and condensation (removal of H2O) reaction between 2-aminobenzyl alcohols and secondary alcohols.
- Das, Kalicharan,Mondal, Avijit,Srimani, Dipankar
-
supporting information
p. 10582 - 10585
(2018/09/25)
-
- Method for preparing benzothiazole compound through microwave catalysis in water phase
-
The invention discloses a method for preparing a benzothiazole compound through/under microwave catalysis in a water phase. A water-soluble coordination compound is used as a catalyst, and a reactionof inorganic sulfide, 2-iodoaniline and aldehyde is efficiently catalyzed through microwaves in a pure water phase. The method for preparing the benzothiazole compound is environmentally friendly, convenient to operate, safe, cheap and efficient. Compared with the prior art, the method is applied to a large quantity of functional groups, high in yield, simple to operate, safe, low in cost and environmentally friendly and produces a few byproducts.
- -
-
Paragraph 0033
(2018/05/16)
-
- Visible-light-promoted synthesis of benzothiazoles from 2-aminothiophenols and aldehydes
-
A visible-light-promoted synthesis of benzothiazoles from 2-aminothiophenols and aldehydes has been developed. A wide range of aromatic, heteroaromatic and aliphatic aldehydes were successfully applied. The benzothiazole products were prepared in good yields. The reaction was carried out in the absence of transition-metal catalysts and extra additives. A radical reaction pathway was proposed.
- Ye, Lin-miao,Chen, Jie,Mao, Peng,Mao, Zhi-feng,Zhang, Xue-jing,Yan, Ming
-
supporting information
p. 874 - 876
(2017/02/18)
-
- Novel Cu(0)-Fe3O4@SiO2/NH2cel as an Efficient and Sustainable Magnetic Catalyst for the Synthesis of 1,4-Disubstituted-1,2,3-triazoles and 2-Substituted-Benzothiazoles via One-Pot Strategy in Aqueous Media
-
A novel, air stable, water dispersible and efficient magnetic catalyst based on copper nanoparticles onto ethylene diamine functionalized inorganic/organic composite [Cu(0)-Fe3O4@SiO2/NH2cel] has been prepared. Functionalization of inorganic/organic composite by ethylene diamine imparts desirable chemical functionality and enables the generation of active sites for the immobilization of Cu(0) nanoparticles. The novel catalyst system has been well characterized by various techniques like FTIR, TGA, XRD, SEM, HRTEM, EDX, ICP-AES, UV-Vis and VSM. Further, Cu(0)-Fe3O4@SiO2/NH2cel opens up a new avenue to introduce a very useful and efficient catalytic system for the one-pot synthesis of 1,4-disubstituted-1,2,3-triazoles via 1,3-dipolar cycloaddition of terminal acetylenes to azides, generated in situ from anilines in water at room temperature, and one-pot three component reaction of 2-iodoaniline, aldehyde and thiourea as sulphur source for the synthesis of 2-substituted-benzothiazole derivatives in water. The novel heterogeneous magnetic catalyst offers recyclability without significant deterioration in catalytic activity and can be easily recovered using an external magnet, thus making it eco-friendly and economical to perform the desired transformations.
- Bhardwaj, Madhvi,Jamwal, Babita,Paul, Satya
-
p. 629 - 644
(2016/02/26)
-
- Photoinduced Copper-Catalyzed C-H Arylation at Room Temperature
-
Room-temperature azole C-H arylations were accomplished with inexpensive copper(I) compounds by means of photoinduced catalysis. The expedient copper catalysis set the stage for site-selective C-H arylations of non-aromatic oxazolines under mild reaction conditions, and provides step-economical access to the alkaloid natural products balsoxin and texamine. Copper light: Room-temperature C-H arylations of heteroarenes were accomplished with inexpensive copper compounds by photoinduced catalysis. The expedient copper catalysis leads to site-selective C-H arylations of non-aromatic oxazolines under mild reaction conditions, and provides step-economical access to the alkaloid natural products balsoxin and texamine.
- Yang, Fanzhi,Koeller, Julian,Ackermann, Lutz
-
supporting information
p. 4759 - 4762
(2016/04/19)
-
- Method for catalytic synthesis of 2-substituted benzothiazole compound by utilizing Yb/MCM-41 molecular sieve-based catalyst
-
The invention relates to a method for the catalytic synthesis of a 2-substituted benzothiazole compound by utilizing a Yb/MCM-41 molecular sieve-based catalyst. The method comprises the steps of (a) subjecting 2-amino thiophenol, an aldehyde compound and
- -
-
Paragraph 0090; 0091; 0092; 0093; 0094
(2016/10/17)
-
- An iron and copper system catalyzed C-H arylation of azoles with arylboronic acids
-
An efficient, environmentally friendly, and economical new method for arylation reactions of azoles with arylboronic acids via copper-iron-catalyzed C-H and C-B bond activation has been developed. The protocol tolerates a series of functional groups, such as methoxy, nitro, cyano, chloro, and trifluoromethyl groups.
- Hu, Wei-Ye,Wang, Pei-Pei,Zhang, Song-Lin
-
supporting information
p. 42 - 48
(2015/02/02)
-
- Room-temperature ligand-free Pd/C-catalyzed C-S bond formation: Synthesis of 2-substituted benzothiazoles
-
The synthesis of 2-substituted benzothiazoles has been achieved via cyclization of o-iodothiobenzanilide derivatives using Pd/C as the catalyst at room temperature. The protocol is ligand-free, additive-free, and high-yielding and involves very mild conditions.
- Cheng, Yannan,Peng, Qian,Fan, Weigang,Li, Pixu
-
p. 5812 - 5819
(2014/07/08)
-
- Iron phthalocyanine as an efficient and versatile catalyst for N-alkylation of heterocyclic amines with alcohols: One-pot synthesis of 2-substituted benzimidazoles, benzothiazoles and benzoxazoles
-
An efficient and versatile iron phthalocyanine catalyzed method has been developed for N-alkylation of various amines with alcohols. Readily available alcohols were used as alkylating agents for direct N-alkylation of aminobenzothiazoles, aminopyridines and aminopyrimidines. N-Alkylation of ortho-substituted anilines (-NH2, -SH and -OH) led to the synthesis of 2-substituted benzimidazoles, benzothiazoles and benzoxazoles in one pot.
- Bala, Manju,Verma, Praveen Kumar,Sharma, Upendra,Kumar, Neeraj,Singh, Bikram
-
supporting information
p. 1687 - 1693
(2013/09/24)
-