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1.
Fluorinated phenethyl bromides 1,2 , and 3 , prove to be totally inert under Ritter reaction conditions in the presence of either SnCl4 or AgNO3, due to the strong deactivation by the gem‐difluoro unit. Subjecting 2‐bromo‐1‐fluoro‐1‐phenylethane to SnCl4 in MeCN at elevated temperatures led to formation of 2‐methyl‐4‐phenyl‐4,5‐dihydrooxazole. 相似文献
2.
Mohammad Yazdanbakhsh Mohammad Hakimi Majid M. Heravi Roland Boese 《无机化学与普通化学杂志》2006,632(14):2201-2203
The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione with AgNO3 in methanol led to the complex [Ag(ATT)2]NO3 ( 2 ). 2 was characterized by elemental analyses, IR, 1HNMR and Raman spectroscopy as well as single‐crystal X‐ray diffraction. Crystal data for 2 at ?70 °C: space group P21/n with a = 1356.7(12), b = 770.4(7), c = 1475.2(12) pm, β = 111.730(15)°, Z = 4, R1 = 0.0402. 相似文献
3.
Nataliya F. Lazareva Tamara I. Vakul'skaya Alexander I. Albanov Vadim A. Pestunovich 《应用有机金属化学》2006,20(10):696-705
The introduction of the organosilicon substituent into the α‐position of an amino group results in cardinal change of the amine reactivity irrespective of the coordination state of silicon. Amines R2NCH2SiX3 [R = Me, Et, PhCH2, CH2SiX3; SiX3 = SiMe3, Si(OEt)3, Si(OCH2CH2)3N] easily react with AgNO3, to give the corresponding ammonium salts (R2NH+ CH2SiX3)·NO3?. At the same time, Ag(I) is reduced to Ag(0). The interaction of N‐methyl‐N,N‐bis(silatranylmethyl)amine with AgNO3 has been investigated by EPR spectroscopy. It was proven that the reaction involved a single electron transfer stage with the formation of cation radical of this amine. A mechanism of the reaction is proposed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
4.
Reaction of thiocarbohydrazide with glyoxolic acid monohydrate led to 4‐amino‐3‐thioxo‐3,4‐dihydro‐1,2,4‐triazin‐5(2H)‐one (AHTTO, 1 ). Treatment of 1 with AgNO3 and PPh3 gave thecomplexes [(PPh3)2Ag2(μ‐N,S‐AHTTO)2](NO3)2 ( 2 ) and [(PPh3)2Ag(AHTTO)]NO3 · MeOH ( 3 ) was obtained under different conditions. All the compounds have been characterized by elemental analyses, IR spectroscopy and X‐ray diffraction studies. 相似文献
5.
A series of novel 4‐(2‐(4‐bromophenyl)‐1,2,3‐triazol‐4‐yl)‐3,4‐dihydropyrimidin‐2(1H)‐ones/thiones were prepared by condensing 2‐(4‐bromophenyl)‐4‐formyl‐1,2,3‐triazole with 1,3‐dicarbonyl compound and urea or thiourea using Mg(NO3)2 as an efficient and cheap catalyst. The satisfactory results were obtained with excellent yields and short reaction time. J. Heterocyclic Chem., (2010). 相似文献
6.
A series of silver(I) supramolecular complexes, namely, {[Ag(L24)](NO3)}n ( 1 ), [Ag2(L24)(NO2)2]n ( 2 ), and {[Ag1.25(L24)(DMF)](PF6)1.25}n ( 3 ) were prepared by the reactions of 1‐(2‐pyridyl)‐2‐(4‐pyridyl)‐1,2,4‐triazole (L24) and silver(I) salts with different anions (AgNO3, AgNO2, AgPF6). Single‐crystal X‐ray diffraction indicates that 1 – 3 display diverse supramolecular networks. The structure of dinuclear complex 1 is composed of a six‐membered Ag2N4 ring with the Ag ··· Ag distance of 4.4137(3) Å. In complex 2 , the adjacent AgI centers are interlinked by L24 ligands into a 1D chain, the adjacent of which are further extended by the bridged nitrites to construct a 2D coordination architecture. Complex 3 shows a 3D (3,4)‐connected framework, which is generated by the linkage of L24 ligands. All complexes were characterized by IR spectra, elemental analysis, and powder X‐ray diffraction. Notably, a structural comparison of the complexes demonstrates that their structures are predominated by the nature of anions. Additionally, 1 and 2 show efficient dichromate (Cr2O72–) capture in water system, which can be ascribed to the anion‐exchange. 相似文献
7.
A simple and eco‐friendly method for the preparation of 1,5‐diaryl‐3‐(arylamino)‐1H‐pyrrol‐2(5H)‐ones via the cyclo‐condensation reaction of aldehydes, amines and ethyl pyruvate in the presence of silica supported ferric chloride (SiO2‐FeCl3) as reusable heterogeneous catalyst is described. The present methodology offers several advantages such as excellent yields, simple procedure and short reaction times. 相似文献
8.
Oxidation of some derivatives of 4b,9b–dihydroxyindeno[1,2‐b]benzofuran‐10‐one have been investigated in detail using lead(IV) acetate in acetic acid under reflux conditions and periodic acid in aqueous ethanol at room temperature. We realized that during the first 5–15 minutes of the oxidation reactions in lead(IV) acetate/acetic acid system, 3H,3’H‐spiro[benzofuran‐2,1′‐isobenzofuran]‐3,3′‐dione derivatives have been synthesized chemo selectively, while, if the reaction mixtures stirred for additional 3 hours, the main products would be 2‐(2‐(Methoxycarbonyl)‐3‐oxo‐2,3‐dihydrobenzofuran‐2‐yl)benzoic acids. Moreover, room temperature oxidation of 4b,9b–dihydroxyindeno[1,2‐b]benzofuran‐10‐ones by periodic acid (H5IO6), leads to the formation of 3H,3’H‐spiro[benzofuran‐2,1′‐isobenzofuran]‐3,3′‐dione derivatives in good to excellent yields. 相似文献
9.
An efficient route to 2′,3′‐dihydro‐2′‐thioxospiro[indole‐3,6′‐[1,3]thiazin]‐2(1H)‐one derivatives is described. It involves the reaction of isatine, 1‐phenyl‐2‐(1,1,1‐triphenyl‐λ5‐phosphanylidene)ethan‐1‐one, and different amines in the presence of CS2 in dry MeOH at reflux (Scheme 1). The alkyl carbamodithioate, which results from the addition of the amine to CS2, is added to the α,β‐unsaturated ketone, resulting from the reaction between 1‐phenyl‐2‐(1,1,1‐triphenyl‐λ5‐phosphanylidene)ethan‐1‐one and isatine, to produce the 3′‐alkyl‐2′,3′‐dihydro‐4′‐phenyl‐2′‐thioxospiro[indole‐3,6′‐[1,3]thiazin]‐2(1H)‐one derivatives in excellent yields (Scheme 2). Their structures were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. 相似文献
10.
Various arylboronic acids reacted with activated alkenes in the presence of [Ni(dppe)Br2], ZnCl2, and H2O in CH3CN at 80 °C to give the corresponding Mizoroki–Heck‐type addition products in good to excellent yields. Furthermore, 1 equivalent of the hydrogenation product of the activated alkene was also produced. By tuning the ligands of the nickel complexes and the reaction conditions, Michael‐type addition was achieved in a very selective manner. Thus, various p‐ and o‐substituted arylboronic acids or alkenylboronic acid reacted smoothly with activated alkenes in CH3CN at 80 °C for 12 h catalyzed by Ni(acac)2, P(o‐anisyl)3, and K2CO3 to give the corresponding Michael‐type addition products in excellent yields. However, for m‐substituted arylboronic acids, the yields of Michael‐type addition products are very low. The cause of this unusual meta‐substitution effect is not clear. By altering the solvent or phosphine ligand, the product yields for m‐substituted arylboronic acids were greatly improved. In contrast to previous results in the literature, the present catalytic reactions required water for Mizoroki–Heck‐type products and dry reaction conditions for Michael‐type addition products. Possible mechanistic pathways for both addition reactions are proposed. 相似文献
11.
Qing‐Xia Zhang Yao Li Jie Wang Chen Yang Cheng‐Jun Liu Xin Li Jin‐Pei Cheng 《Angewandte Chemie (International ed. in English)》2020,59(11):4550-4556
The enantioselective ketimine–ene reaction is one of the most challenging stereocontrolled reaction types in organic synthesis. In this work, catalytic enantioselective ketimine–ene reactions of 2‐aryl‐3H‐indol‐3‐ones with α‐methylstyrenes were achieved by utilizing a B(C6F5)3/chiral phosphoric acid (CPA) catalyst. These ketimine–ene reactions proceed well with low catalyst loading (B(C6F5)3/CPA=2 mol %/2 mol %) under mild conditions, providing rapid and facile access to a series of functionalized 2‐allyl‐indolin‐3‐ones with very good reactivity (up to 99 % yield) and excellent enantioselectivity (up to 99 % ee). Theoretical calculations reveal that enhancement of the acidity of the chiral phosphoric acid by B(C6F5)3 significantly reduces the activation free energy barrier. Furthermore, collective favorable hydrogen‐bonding interactions, especially the enhanced N?H???O hydrogen‐bonding interaction, differentiates the free energy of the transition states of CPA and B(C6F5)3/CPA, thereby inducing the improvement of stereoselectivity. 相似文献
12.
Prof. Dr. Hai‐Bin Zhu Shu‐Ying Zhang Xin Lu Wen‐Na Yang Prof. Dr. Shao‐Hua Gou Jing Chen 《无机化学与普通化学杂志》2011,637(10):1423-1426
Reactions of the ligand 2 ‐ MTPP [2‐MTPP = 2‐(methylthio)‐4‐(pyridin‐2‐yl)pyrimidine] with AgNO3 and CuI produced dinuclear silver(I) ( 1 ) and copper(I) ( 2 ) complexes, respectively. Both complexes adopt a chair‐like structure in which two 2 ‐ MTPP ligands and two metal ions are joined together through M–N and M–S coordination bonds. The luminescence properties of both complexes were investigated in solid state at room temperature. 相似文献
13.
Di Sun Geng‐Geng Luo Na Zhang Rong‐Bin Huang Lan‐Sun Zheng 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(12):m478-m480
The solution reaction of AgNO3 and 2‐aminopyrazine (apyz) in a 1:1 ratio gives rise to the title compound, [Ag2(NO3)2(C4H5N3)2]n, (I), which possesses a chiral crystal structure. In (I), both of the crystallographically independent AgI cations are coordinated in tetrahedral geometries by two N atoms from two apyz ligands and two O atoms from nitrate anions; however, the AgI centers show two different coordination environments in which one is coordinated by two O atoms from two different symmetry‐related nitrate anions and the second is coordinated by two O atoms from a single nitrate anion. The crystal structure consists of one‐dimensional AgI–apyz chains, which are further extended by μ2‐κ2O:O nitrate anions into a two‐dimensional (4,4) sheet. N—H...O and Capyz—H...O hydrogen bonds connect neighboring sheets to form a three‐dimensional supramolecular framework. 相似文献
14.
Abdolali Alizadeh Hamid Reza Esmaili zand Vahid Saberi Javad Mokhtari 《Helvetica chimica acta》2013,96(12):2240-2244
An efficient approach for the preparation of functionalized 5‐aryl‐3‐(methylsulfanyl)‐1H‐pyrazoles 2 is described. This three‐component reaction between benzaldehydes 1 , NH2NH2?H2O, and 1,1‐bis(methylsulfanyl)‐2‐nitroethene proceeds in EtOH under reflux conditions in good‐to‐excellent yields. The structures of 2 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS). A plausible mechanism for this type of reaction is proposed (Scheme 2). 相似文献
15.
Di Sun Geng‐Geng Luo Na Zhang Rong‐Bin Huang Lan‐Sun Zheng 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(11):m418-m421
The ultrasonic reaction of AgNO3, 4,4′‐bipyridine (bipy) and naphthalene‐2,6‐dicarboxylic acid (H2NDC) gives rise to the title compound, {[Ag2(C10H8N2)2](C12H6O4)·4H2O}n. The NDC dianion is located on an inversion centre. The AgI centre is coordinated in a linear manner by two N atoms from two bipy ligands. The crystal structure consists of one‐dimensional AgI–bipy cationic chains and two‐dimensional NDC–H2O anionic sheets, constructed by coordination bonds and supramolecular interactions, respectively. 相似文献
16.
AgNO3 Catalyzed Regio‐Selective Synthesis of 3‐Alkyl/Aryl‐idene‐3,4‐dihydro‐4‐tosyl‐2H‐1,4‐Benzoxazine: Novel Anti‐Tubercular Scaffolds
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Sivanandhan Karunanidhi Rajshekhar Karpoormath Milan Bera Rajesh A. Rane Mahesh B. Palkar 《Journal of heterocyclic chemistry》2016,53(5):1611-1616
A facile and efficient method for the construction of 3‐alkyl/aryl substituted 1,4‐benzoxazine and benzoxazepine via AgNO3 catalyzed cyclization of propargyloxy sulfonamides and their anti‐tubercular activity against Mycobacterium tuberculosis H37RV is described. This cyclization proceeds through 6‐exo‐dig manner to generate the products in moderate to good yields. 相似文献
17.
The reaction of dialkyl acetylenedicarboxylates 4 with 1‐aryl‐2‐[(3‐arylquinoxalin‐2(1H)‐ylidene)ethanones 3 in the presence of Ph3P leads to dialkyl (2Z)‐2‐[(E)‐1‐aryl‐2‐(3‐arylquinoxalin‐2‐yl)ethenyl]but‐2‐enedioates 1 in good yields. 相似文献
18.
An efficient approach for the preparation of functionalized 2‐aryl‐2,5‐dihydro‐5‐oxo‐4‐[2‐(phenylmethylidene)hydrazino]‐1H‐pyrroles is described. The four‐component reaction between aldehydes, NH2NH2?H2O, dialkyl acetylenedicarboxylates, and 1‐aryl‐N,N′‐bis(arylmethylidene)methanediamines proceeds in EtOH under reflux in good‐to‐excellent yields (Scheme 1). The structures of 4 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS, and, in the case of 4f , by X‐ray crystallography). A plausible mechanism for this type of reaction is proposed (Scheme 2). 相似文献
19.
Chin‐Sheng Chao Chen‐Wei Li Min‐Chun Chen Shih‐Sheng Chang Kwok‐Kong Tony Mong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(41):10972-10982
This study develops an operationally easy, efficient, and general 1,2‐trans β‐selective glycosylation reaction that proceeds in the absence of a C2 acyl function. This process employs chemically stable thioglycosyl donors and low substrate concentrations to achieve excellent β‐selectivities in glycosylation reactions. This method is widely applicable to a range of glycosyl substrates irrespective of their structures and hydroxyl‐protecting functions. This low‐concentration 1,2‐trans β‐selective glycosylation in carbohydrate chemistry removes the restriction of using highly reactive thioglycosides to construct 1,2‐trans β‐glycosidic bonds. This is beneficial to the design of new strategies for oligosaccharide synthesis, as illustrated in the preparation of the biologically relevant β‐(1→6)‐glucan trisaccharide, β‐linked Gb3 and isoGb3 derivatives. 相似文献
20.
《中国化学会会志》2017,64(7):764-776
An efficient acid‐catalyzed synthesis of some bis, tris, and tetrakis(indolyl)methanes, 3,4‐dihydropyrimidin‐2(1H )‐ones, and 2‐aryl‐1H ‐benzothiazoles is reported using NaY zeolite functionalized by sulfamic acid/Cu(OAc )2 (NaY zeolite‐NHSO3H /Cu(OAc )2) in excellent yield. The heterogeneous catalyst has a simple work‐up procedure and could be recycled and reused for six reaction cycles. 相似文献