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91.
Lukas J. Gooßen Prof. Dr. Käthe Gooßen Dr. Corneliu Stanciu Dr. 《Angewandte Chemie (International ed. in English)》2009,48(20):3569-3571
Crucial breakthroughs in the activation of the C(aryl)? O bond of phenol derivatives were achieved almost simultaneously by two research groups (see scheme; Cy=cyclohexyl). Garg et al. coupled a range of aryl pivalates with arylboronic acids to give unsymmetrical biaryls. Shi et al. achieved this through C(aryl)? O activation of aryl carboxylates; the best results for the coupling of aryl boroxines were again obtained with aryl pivalates.
92.
Qianwen Ye Hongqiang Ye Dongping Cheng Xiaonian Li Xiaoliang Xu 《Tetrahedron letters》2018,59(26):2546-2549
Catalyzed by Ir(dFCF3ppy)2(dtbbpy)PF6, several aroyl methylidenemalonates were synthesized in good to excellent yields via visible light photoredox-catalyzed the oxidative ring-opening of cyclopropenyl carboxylate derivatives. The possible mechanism of oxidative quenching cycle was proposed. 相似文献
93.
94.
One‐Pot Synthesis of (1,2,3‐Triazolyl)methyl 3,4‐Dihydro‐2‐oxo‐1H‐pyrimidine‐5‐carboxylates as Potentially Active Antimicrobial Agents 下载免费PDF全文
Minoo Dabiri Peyman Salehi Mahboubeh Bahramnejad Majid Koohshari Atousa Aliahmadi 《Helvetica chimica acta》2014,97(3):375-383
A simple and efficient one‐pot four‐component procedure has been developed for the synthesis of a wide range of compounds containing the (triazolyl)methyl oxo‐pyrimidine‐carboxylate system from propargyl β‐keto esters, various azides, aldehydes, and urea in the presence of catalytic amounts of (AcO)2Cu/sodium ascorbate in AcOH. The method worked well with different aryl and heteroaryl aldehydes, and for a variety of substituents in the triazolyl part of the molecule. The antimicrobial activities of the products were evaluated against two Gram‐positive and Gram‐negative bacteria, and one fungus. Compound 5j was active against Staphylococcus aureus and Candida albicans. 相似文献
95.
Issa Yavari Zinatossadat Hossaini Samereh Seyfi Faezeh Shirgahi‐Talari 《Helvetica chimica acta》2008,91(6):1177-1180
An efficient synthesis of ethyl 2‐(dimethylamino)‐1,3‐thiazole‐4‐carboxylates is described via a four‐component reaction between acid chlorides, tetramethylthiourea, ethyl bromopyruvate, and ammonium thiocyanate. 相似文献
96.
Yan Y Blake AJ Lewis W Barnett SA Dailly A Champness NR Schröder M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(40):11162-11170
Three isostructural metal-organic polyhedral cage based frameworks (denoted NOTT-113, NOTT-114 and NOTT-115) with (3,24)-connected topology have been synthesised by combining hexacarboxylate isophthalate linkers with {Cu(2)(RCOO)(4)} paddlewheels. All three frameworks have the same cuboctahedral cage structure constructed from 24 isophthalates from the ligands and 12 {Cu(2)(RCOO)(4)} paddlewheel moieties. The frameworks differ only in the functionality of the central core of the hexacarboxylate ligands with trimethylphenyl, phenylamine and triphenylamine moieties in NOTT-113, NOTT-114 and NOTT-115, respectively. Exchange of pore solvent with acetone followed by heating affords the corresponding desolvated framework materials, which show high BET surface areas of 2970, 3424 and 3394 m(2) g(-1) for NOTT-113, NOTT-114 and NOTT-115, respectively. Desolvated NOTT-113 and NOTT-114 show high total H(2) adsorption capacities of 6.7 and 6.8 wt%, respectively, at 77 K and 60 bar. Desolvated NOTT-115 has a significantly higher total H(2) uptake of 7.5 wt% under the same conditions. Analysis of the heats of adsorption (Q(st)) for H(2) reveals that with a triphenylamine moiety in the cage wall, desolvated NOTT-115 shows the highest value of Q(st) for these three materials, indicating that functionalisation of the cage walls with more aromatic rings can enhance the H(2)/framework interactions. In contrast, measurement of Q(st) reveals that the amine-substituted trisalkynylbenzene core used in NOTT-114 gives a notably lower H(2)/framework binding energy. 相似文献
97.
Using ferrocenyl carboxylates as functional ligands, we synthesized a mononuclear complex [Zn(η2-OOCCHCHFc)2(CH3OH)2] (1) and a binuclear complex [Cd(bafca)2(H2O)2]2 (2) (bafca− = α-benzamido-β-ferrocenylacrylic carboxylate) as precursor complexes. Investigation on the substitution reaction of precursor complexes as building blocks in solution-state, four complexes [Zn(OOCCHCHFc)2(bbbm)]n (1a), {[Zn(OOCCHCHFc)(ntb)](CH3OH)} (1b), [Cd(bafca)2(2,2′-bpy)]2 · 9H2O (2a) and {[Cd(bafca)2(bbbm)(CH3OH)2] · 6CH3OH}n (2b) were obtained (bbbm = 1,1-(1,4-Butanediyl)bis-1H-benzimidazole, ntb = N,N-bis(1H-benzimidazol-2-ylmethyl)-1H-Benzimidazole-2-methanamine and 2,2′-bpy = 2,2′-bipyridine). As anticipated, the structural integrity of precursor complexes can be maintained in these four complexes. It indicates that we can synthesize the desired complexes with the destination structures by using precursor complexes as building blocks and choosing appropriate auxiliary ligands. In addition, the electrochemical properties of all complexes were investigated, and it can be seen from the results that half-wave potentials of these complexes are slightly higher than that of the corresponding ligand. 相似文献
98.
With the reaction of bis(1,5‐cyclooctadiene)nickel(0) and trans‐penta‐2,4‐dienoic acid in the presence of tricyclohexylphosphine, a new more general method was developed to synthesize cyclic π3‐allyl‐carboxylato Ni(II) complexes, which are known to be intermediates in the C? C coupling of butadiene and CO2. The cyclic π3‐allyl‐carboxylato Ni(II) complex obtained is tested as a mediator in the electrochemical coupling reaction of butadiene and carbon dioxide. We also demonstrate the dependency on the coordination sphere by using platinum instead of nickel as the metal center. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
99.
吡啶羧酸铬配合物的合成及其生物活性 总被引:3,自引:0,他引:3
报道了3种吡啶羧酸铬配合物的合成,其结构经元素分析、IR、’H—NMR和MS表征。以2-吡啶甲酸铬配合物饲喂猪的试验表明,它是一种很有效的饲料添加剂。 相似文献
100.
《Green Chemistry Letters and Reviews》2013,6(4):355-368
Abstract An efficient and rapid synthesis of an array of naphthyl-substituted cyclohexenone carboxylates, indazolonols, and nitrohydrazones by using activated fly ash as catalyst in dry media is described. All the synthesized compounds were characterized by their melting point, elemental analysis, mass spectrometry, Fourier transform infrared, one-dimensional nuclear magnetic resonance (1H and D2O exchanged 1H and 13C), and two-dimensional homonuclear correlation (HOMOCOR) and heteronuclear single quantum coherence (HSQC) spectroscopic data. Compared to classical conditions, this new protocol had the advantage of excellent yields, mild reaction conditions, simple workup, and short reaction times. Also, the catalyst could be reused up to four runs without any reduction in efficiency, making the process greener and environmentally benign. 相似文献