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The acidic ionic liquids were new catalysts for the one-pot Biginelli reaction coupling of aldehyde, 1,3-dicarbonyl compound, and urea to afford the corresponding dihydropyrimidinones in good yields under solvent-free conditions. The catalysts could be recycled and reused five times without a noticeable decrease in catalytic activity. 相似文献
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AbstractWe developed a facile one-pot procedure for the synthesis of 4,6-diaryl-3,4-dihydropyrimidine-2(1H)-thione under ultrasonic irradiation. The method is based on a three components reaction of aldehydes, ketones, and thiourea under basic conditions affording isolated yields of up to 95% within a reaction time of 30–90?min. 相似文献
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IntroductionInrecentyears ,dihydropyrimidinethionederivativeshaveattractedconsiderableinterestduetotheirpromisingactivitiesasanticarcinogenicagents ,1cardiovasculara gents2 andcalciumchannelblockers .3Inaddition ,somederivativesofdihydropyrimidinethionewer… 相似文献
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Jayashree Nath 《合成通讯》2013,43(20):2976-2982
Borax in the presence of a very small amount of 5 M sulfuric acid efficiently catalyses the three-component condensation of an aldehyde, β-ketoester, and urea or thiourea to afford the corresponding 3,4-dihydropyrimidin-2(1H)-ones or 3,4-dihydropyrimidin-2(1H)-thiones in good to excellent yields under solvent-free conditions at 80 °C. Compared with the classical Biginelli reaction conditions, this new method has the advantage of excellent yield, short reaction time (1–2 h), easy workup, and no use of volatile organic solvent. 相似文献
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Polymer-supported 4-aminoformoyldiphenylammonium triflate (PS-AFDPAT) was used as an effective catalyst for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) via the Biginelli reaction. This immobilized catalyst could be easily recovered by simple filtration and recycled for 10 runs without significant decrease of the catalytic activity. 相似文献
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Ren-Lin Zheng Xiu-Xiu Zeng Hai-Yun He Jun He Sheng-Yong Yang Luo-Ting Yu 《合成通讯》2013,43(10):1521-1531
An improved synthesis of 6-aryl-3-cyanopyridine-2-(1H)-thiones utilizing enaminones as starting materials catalyzed by 1,4-diazabicyclo[2.2.2]octane (DABCO) was described. Moreover, a convenient one-pot conversion of aryl ketones to 6-aryl-3-cyanopyridine-2-(1H)-thiones was also developed in moderate to good yields (up to 80%). 相似文献
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Maryam MOGHADDAS Abolghasem DAVOODNIA Majid M.HERAVI Niloofar TAVAKOLI-HOSEINI 《催化学报》2012,33(4):706-710
A sulfonated carbon material was shown to be a highly efficient,eco-friendly,and recyclable solid acid catalyst for the Biginelli reaction of β-ketoester,aldehyde,and urea or thiourea under solvent-free conditions.It gave 3,4-dihydropyrimidin-2(1H)-ones and-thiones in good to excellent yields.This method has the advantages of a simple procedure with easy work-up,short reaction time,and high yields.The catalyst can be recycled after a simple work-up and was reused four times without substantial reduction in activity. 相似文献
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Iryna O. LebedyevaVictor V. Dotsenko Vladimir V. Turovtsev Sergey G. KrivokolyskoV'yacheslav M. Povstyanoy Mikhaylo V. Povstyanoy 《Tetrahedron》2012,68(47):9729-9737
3-Cyanopyridine-2(1H)-thiones have been shown to react with Biginelli-type ethyl 4-aryl-6-(bromomethyl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates upon heating in DMF giving rise to ethyl 4-aryl-6-{[(3-cyanopyridin-2-yl)thio]methyl}-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates. The latter upon treatment with an excess of NaH or t-BuOK in boiling DMF undergo a tandem Thorpe-Ziegler-type heterocyclization to give pyrido[3″,2″:4′,5′]thieno[2′,3′:5,6]pyrido[4,3-d]pyrimidine derivatives in good yields. Selected compounds were tested for antibacterial and antifungal activity. 相似文献
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Hamid Reza Shaterian Asghar Hosseinian Majid Ghashang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):126-134
An efficient, facile, simple, and green synthetic protocol for the Biginelli reaction has been developed for the preparation of 3,4-dihydropyrimidin-2(1H)-thione derivatives under thermal and microwave irradiation, solvent-free conditions, in the presence of aluminum hydrogen phosphate, Al(H2PO4)3, as an environmentally friendly heterogeneous recyclable catalyst, in high to excellent yields and short reaction time. In addition, the catalyst could be easily recovered from the reaction mixture by simple filtration and reused several times without any loss of activity. 相似文献
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以取代芳醛(1a~1h),乙酰乙酸乙酯(2)和脲(3)为原料,MMT/CuCl2为催化剂,乙醇为溶剂,在超声条件下经Beginelli反应合成了8个3,4-二氢嘧啶-2(1H)-酮衍生物(4a~4h),其结构经1H NMR和IR确证。以4a为例,分别采用单因素法和正交实验法研究了催化剂、溶剂、反应温度、超声时间和物料比r[n(1a): n(2) :n(3)]对4a产率的影响。结果表明:在最优反应条件(1a 2.4 mol, r=1.2 : 1.0 : 1.0, MMT/CuCl220 mol%, EtOH 1 mL,于90 ℃超声15 min)下,4a产率88.4%。 MMT/CuCl2循环使用3次,产率基本不变。 相似文献
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Jacek G. Sośnicki 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1946-1957
Organolithium and Grignard reagents are added to pyrimidine-2(1H)-thione, yielding 4-substituted 3,4-dihydropyrimidine-2-(1H)-thiones. Since the synthetic procedure can be performed on a multigram scale, and since pyrimidine-2(1H)-thione as well as the majority of organometallic reagents are readily available, the process described provides an easy access and complementary to other methods to 4-substituted 3,4-dihydropyrimidine-2-(1H)-thiones. 相似文献
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An efficient and facile synthesis of 4,6-diarylpyrimidin-2(1H)-one via a Biginelli-like reaction of aromatic aldehydes, aromatic ketones, and urea in the presence of NaOH under solvent-free conditions using a heating method has been developed. Compared with the classical reaction conditions, this new synthetic method has the advantages of excellent yields, shorter reaction time, and mild reaction conditions. 相似文献