共查询到20条相似文献,搜索用时 15 毫秒
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Facile Yb(OTf)3 promoted one-pot synthesis of polyhydroquinoline derivatives through Hantzsch reaction 总被引:1,自引:0,他引:1
Yb(OTf)3 catalyzed efficient Hantzsch reaction via four-component coupling reactions of aldehydes, dimedone, ethyl acetoacetate and ammonium acetate at ambient temperature was described as the preparation of polyhydroquinoline derivatives. The process presented here is operationally simple, environmentally benign and has excellent yield. Furthermore, the catalyst can be recovered conveniently and reused efficiently. 相似文献
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A mild and facile method for the synthesis of 3-arylbenzo[f]quinoline-1,2-dicarboxylate derivatives is reported by an imino-Diels-Alder reaction in high yields (76-92%). This procedure includes a novel three-component reaction of aromatic aldehyde, naphthalen-2-amine, and but-2-ynedioate catalyzed by Yb(OTf)3 in toluene. The results are obviously different from those of the simple substituted aniline-involved reactions catalyzed by ZnCl2 or KOH in the literature. 相似文献
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Conjugate addition of indoles and thiols with a variety of electron-deficient olefins mediated by a catalytic amount of Bi(OTf)3 at ambient temperature to afford the corresponding Michael adducts in good to excellent yields with high selectivity is reported. 相似文献
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Rina Ghosh Swarupananda Maiti Arijit Chakraborty Dilip K. Maiti 《Journal of molecular catalysis. A, Chemical》2004,210(1-2):53-57
A new efficient one-pot synthesis of α-amino phosphonates derived from nitro substituted anilines, aldehydes and diethyl phosphite has been carried out by employing 5 mol% of In(OTf)3. The method is equally effective for the generation of α-amino phosphonates from various carbonyl compounds and other amines. 相似文献
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Mingxi Wu 《Journal of fluorine chemistry》2011,132(3):155-159
The difluoromethyl-containing Biginelli dihydropyrimidinone derivatives were synthesized by a one-pot cyclocondensation of ethyl 4,4-difluoroacetoacetate, urea, and a variety of aldehydes in the presence of 5 mol% ytterbium perfluorooctanoate [Yb(PFO)3] under solvent and dehydrating agent free conditions. The comparison of reaction conditions and products was made among the different 1,3-dicarbonyl substrates (ethyl acetoacetate, ethyl 4,4-difluoroacetoacetate and ethyl 4,4,4-trifluoroacetoacetate) for the Biginelli reaction. 相似文献
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1,2,3,5-Tetrasubstituted pyridinium amino acid isodesmosine is a crosslinking amino acid of elastin and is an attractive biomarker for the diagnosis of chronic obstructive pulmonary disease (COPD). Herein, we report an application of the Chichibabin pyridine synthesis to the total synthesis of isodesmosine. Specifically, the appropriate protected lysine and the corresponding aldehyde were reacted using Pr(OTf)3 in H2O/MeOH. 相似文献
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在离子液体BMImPF6中, 用不同的钯催化剂和Lewis酸三氟甲磺酸铜Cu(OTf)2共催化苯乙烯二聚反应, 发现用Pd(OAc)2/Cu(OTf)2作催化剂, Pd/Cu物质的量之比为1~4时, 可高产率高选择性地获得苯乙烯二聚产物1,3-二苯基-1-丁烯. BMImPF6对催化剂有较好的溶解性, 可固定催化剂体系, 使催化剂有效地与产品分离. 同时, α-甲基苯乙烯的二聚反应表明, 室温下不发生反应, 提高温度有利于反应进行. 相似文献
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Wei-Chieh YangXin-An Lu Suvarn S KulkarniShang-Cheng Hung 《Tetrahedron letters》2003,44(42):7837-7840
A triethylsilane-reductive etherification of the trimethylsilyl ethers with a variety of carbonyl compounds in good yields at room temperature employing 0.5 mol% Cu(OTf)2 as an extremely efficient catalyst is described here. 相似文献
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O,O'Diethyl acetals were prepared in high yields under mild conditions via the reaction of triethyl orthoformate with aldehydes and ketones in absolute ethanol in the presence of as low as 0.1 tool% of Yb(OTf)3. Using the same catalyst in THF-H2O, these O,O'-diethyl acetals could be converted to the corresponding carbonyl compounds efficiently. This new protection-deprotection protocol presents the advantages of ease of execution, high efficiency and good chemoselectivity. 相似文献
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2-Aminobenzyl alcohol reacts with an array of ketones in toluene/poly(ethylene glycol) (PEG-2000) at 100 °C in the presence of a palladium catalyst along with KOH under an atmosphere of air to give the corresponding quinolines in good yields. The catalytic system could be recovered and reused five times without any loss of catalytic activity. 相似文献
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Kumkum KumariDushyant Singh Raghuvanshi Viatcheslav JouikovKrishna Nand Singh 《Tetrahedron letters》2012,53(9):1130-1133
An efficient, rapid, and green synthesis of functionalized pyrazoles has been accomplished under solvent-free conditions by the reaction of phenyl hydrazine, aldehydes and ethyl acetoacetate. This approach exploits the synthetic potential of microwave irradiation and scandium triflate combination and offers many advantages such as excellent product yields, shorter reaction time, easy isolation of products, and environmentally benign reaction conditions. 相似文献
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Santosh T. Kadam 《Journal of organometallic chemistry》2009,694(16):2562-381
A very efficient and mild silylation of alcohols and phenols with hexamethyldisilazane (HMDS) at rt is developed using Bi(OTf)3 as the catalyst. Primary, secondary and tertiary alcohols as well as phenols are excellently converted into corresponding TMS ethers in a very short reaction time. This procedure can also be applied to large scale silylation for industrial application. 相似文献
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Madabhushi Sridhar Mallu Kishore Kumar ReddyVangipuram Venkata Sairam Jillella RaveendraKondal Reddy Godala Chinthala NarsaiahBeeram China Ramanaiah Cirandur Suresh Reddy 《Tetrahedron letters》2012,53(27):3421-3424
An efficient method for the preparation of nitriles directly from aldehydes by reaction with AHA using Bi(OTf)3 as the catalyst is described. Bi(OTf)3 is shown to be an efficient catalyst also for the conversion of aldoximes into nitriles. 相似文献