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731.
P. Narsimha Reddy G. V.Panakal Rao M. Kanakalingeswara Rao B. Rajitha 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2279-2285
Acrolyl furochromen-2-ones (3a–i) obtained in good yields on microwave irradiation of furochromen-2-one (1) with various simple and substituted aromatic aldehydes (2a–i). 3a–g on cyclo dehydration with thiourea in domestic microwave oven furnished tetrahydro thiaxopyrimidine furochromen-2-ones 4a–i in high yields. The structures of the newly synthesized compounds were established on the basis of analytical and spectral data, IR, and 1H NMR. 相似文献
732.
《Tetrahedron》2014,70(21):3385-3389
This work reported that Suzuki–Miyaura coupling reactions of arylboronic acid with aryl bromide or iodides were mediated by Pd(OAc)2 and 4-(benzylthio)-N,N,N-trimethylbenzenammonium chloride in the presence of Na2CO3 in water under the mild conditions. The corresponding Suzuki–Miyaura coupling products were obtained in good to excellent yields. 相似文献
733.
734.
Ullmann-type C–N coupling reaction has been developed for the synthesis of 1-aryl indole derivatives by indoles and aryl halides in the presence of CuI/metformin (CuI/Met) in DMF. This method is very easy, rapid, and high yielding reaction for the synthesis of 1-aryl indoles. In particular, the metformin, which is used as ligand, is inexpensive and nontoxic that is considered to be relatively environmentally benign. 相似文献
735.
A facile route toward substituted aryl diarylvinyl ethers 4 is developed from CuI-mediated cross-coupling reaction of substituted phenols 2 with diarylvinyl bromides 3 in the presence of various bidentate-based ligands in DMF. Skeleton 3 is prepared by Yan’s bromomethylenation of diarylketones 1 with CHBr3–TiCl4–Mg in the co-solvent of DME and CH2Cl2. The synthetic route obtains moderate yields from the one-step operation and the key structure of 4k is confirmed by X-ray crystallographic analysis. The CADD docking experiments of 4k have been included. 相似文献
736.
Microwave accelerated and expedited cyclocondensation reactions of 2-(3-aryl-1H-pyrazol-5-yl)anilines (4) with diverse aryl aldehydes/triethyl orthoformate in water/MeCN (route D) and internal cyclocondensation and aromatization of 5-(2-aminophenyl)-4,5-dihydro-3-arylpyrazole-1-carbaldehyde (7) under MeOH (route E) for the synthesis of a series of pyrazolo[1,5-c]quinazolines and their derivatives (1a–1q) are reported. 相似文献
737.
Copper‐Catalyzed Cross‐CouplingLigand‐Free Conditions Reaction of Thiols with Aryl Iodides under
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Yu‐Ting Huang Wan‐Ting Tsai Satpal Singh Badsara Chien‐Ching Chan Chin‐Fa Lee 《中国化学会会志》2014,61(9):967-974
Commercially available CuO powder is found to be a suitable catalyst for C‐S coupling reaction between aryl‐ and alkyl thiols and aryl iodides. Functional groups including halides, ketone, unprotected amine and heterocycles were tolerated by the reaction conditions employed. 相似文献
738.
A simple, efficient, and inexpensive copper catalyzed protocol has been developed for cross-coupling of indoles with aryl halides by using glycerol as a green recyclable solvent and DMSO as an additive. The reaction was carried out at low catalyst loading furnishing various N-aryl indoles in good to excellent yield. This copper/glycerol mixture was recycled up to four runs without any loss in its catalytic activity. 相似文献
739.
A new library of pyrano[c]chromenes containing an aroyl group has been synthesized by a novel multicomponent process involving the reaction of various aryl glyoxals with 4-hydroxycoumarin and malononitrile. The reactions were catalyzed efficiently by ammonium dihydrogen phosphate to yield the desired products in good to excellent yields. 相似文献
740.
An efficient and simple ligand derived from phthalandione was used for palladium catalyzed Suzuki coupling reaction in water/ethanol (V/V = 2/1) under aerobic conditions. The reaction exhibited a high catalytic efficiency even with lower Pd loading (0.002 mol %). In this work, the catalyst could be successfully used in coupling reaction between various aryl halides with phenylboronic acid in excellent yields with high turnover number (TON) (the maximal TON was up to 49,000 for the reaction of bromobenzene with phenylboronic acid). Moreover, this new ligand had been elucidated by 1H NMR, 13C NMR and X-ray crystal diffraction. 相似文献