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91.
Mohammad Navid Soltani Rad Somayeh Behrouz Abdollah Movahedian Mohammad Mahdi Doroodmand Younes Ghasemi Sara Rasoul‐Amini Abdol‐Rasoul Ahmadi Gandomani Ramin Rezaie 《Helvetica chimica acta》2013,96(4):688-701
A facile and simple protocol for the 1,3‐dipolar cycloaddition of organic azides with terminal alkynes catalyzed by doped nano‐sized Cu2O on melamine? formaldehyde resin (nano‐Cu2O? MFR) as a new and convenient heterogeneous catalyst is described. In this method, ‘click’ cycloaddition of various structurally diverse β‐azido alcohols and alkynes in the presence of nano‐Cu2O? MFR in H2O/THF 1 : 2 furnished the corresponding 1,4‐disubstituted 1H‐1,2,3‐triazole adducts 1a – 1o in good to excellent yields at room temperature (Scheme and Table 3). The nano‐Cu2O? MFR was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), inductively coupled plasma (ICP) analysis, and FT‐IR. The nano‐Cu2O? MFR could be easily recovered and recycled from the reaction mixture and reused for many consecutive trials without significant decrease in activity (Table 4). The in vitro antibacterial activities of all synthesized compounds were tested on several Gram‐positive and/or Gram‐negative bacteria (Table 5). The results demonstrate the promising antibacterial activity for some of the synthesized compounds. 相似文献
92.
A facile and efficient method for dehydration of aldoximes into nitriles using N-(p-toluenesulfonyl) imidazole (TsIm) is described. In this method, aldoximes were refluxed with TsIm in the presence of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU) in dimethylformamide (DMF) to afford the corresponding nitriles in good yields. This methodology is highly efficient for various structurally diverse aldoximes including aromatic, heteroaromatic, and aliphatic oximes. A plausible mechanism for the conversion of aldoxime into nitriles using TsIm/DBU is explained. 相似文献
93.
A simple, efficient and practical procedure for the Biginelli reaction using zinc oxid (ZnO) as a novel and reusable catalyst is described under solvent-free conditions in high yields. The use of this agent is characterized by remarkable reactivity, moderate costs, low toxicity and simple work up procedures. 相似文献
94.
Thiols can be readily converted to their corresponding nitrosothiols with a combination of oxalic acid and sodium nitrite in t-butanol at room temperature (26-30°C). The reaction mixture could be solidified with decreasing its temperature to, 15°C and was stored for several days without any destruction of the nitrosothiols. 相似文献
95.
A simple and convenient method for the synthesis of N-substituted-4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyramides has been reported. Several aromatic and aliphatic amide derivatives of 4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyric acid were prepared in 60–81% yields by refluxing it with different phosphazo compounds in toluene for approximately 1 h. 相似文献
96.
Piperazine supported on amorphous silica (KG-60-piperazine) as a basic catalyst acts in the Gewald three-component reaction of some aldehydes and ketones with malononitrile as well as ethyl cyanoacetate. The catalyst shows general utility with a variety of starting carbonyl compounds. Moreover, the catalyst can be reused for four additional cycles without significant loss of the activity. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
97.
An efficient method for synthesis of various tetrasubstituted imidazoles, using trifluoroacetic acid (TFA) as a catalytic support, by four-component condensation of benzil, aldehydes, amines, and ammonium acetate under microwave-irradiated, solvent-free conditions is described. 相似文献
98.
Mohammad Ghafarzadeh Ebrahim Saeedian Moghadam Fereshteh Faraji 《Journal of heterocyclic chemistry》2013,50(4):754-757
Dibenzo[b,f][1,4]oxazepine derivatives were synthesized in good yields and short reaction times by the reaction of 2‐chlorobenzaldehydes and 2‐aminophenoles in basic conditions under microwave irradiation. 相似文献
99.
100.
Mohammad Ali Zolfigol Peyman Salehi Arash Ghorbani-Choghamarani Maliheh Safaiee Mozhgan Shahamirian 《合成通讯》2013,43(11):1817-1823
Silica chromate easily converts 1,4‐dihydropyridines to their corresponding pyridines in the presence of NaHSO4 · H2O and wet SiO2 in dichloromethane at room temperature in good to excellent yields. 相似文献