共查询到20条相似文献,搜索用时 125 毫秒
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以硝基甲烷和四醛为原料,在碱性条件下经烷基羟基化和溴化两步合成2-溴-2-硝基-1,3-二丙二醇,考虑了烷基羟基化反应,溴化反应温度,时间,对产品收率的影响.收率可达78.6% 相似文献
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以冰乙酸为溶剂,以5-叔丁基-2-羟基苯甲醛和溴素为原料,合成了3-溴-5-叔丁基-2-羟基苯甲醛。考察了溶剂、反应温度、物料比、反应时间等对3-溴-5-叔丁基-2-羟基苯甲醛收率的影响,合成的优化工艺条件为:n(5-叔丁基-2-羟基苯甲醛)∶n(溴素)=1∶1.1,反应温度60℃,反应时间10 h,在此工艺下,收率可达到88.2%,产品经MS、1H NMR确认。 相似文献
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以2,4-二羟基二苯甲酮为原料,经醚化、酯化反应合成有机中间体2-(4-苯甲酰基-3-羟基苯氧基)丙烯酸乙酯;并对其反应的工艺条件进行研究。研究结果表明:反应温度、催化剂的用量和聚合物抑制剂对收率有明显的影响。由此得出反应的适宜条件是:反应温度为150℃;催化剂用量为1.2g;使用聚合物抑制剂收率可达80.5%。 相似文献
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以2,5-二羟基苯甲酸为原料,经酯化、取代、多聚磷酸催化傅克烷基化、酯水解4步反应制备目标化合物,4步反应总收率52. 5%。其结构及中间体经1HNMR、13CNMR和ESI-MS确证。并分别对每一步影响产物收率的因素进行了研究。确定酯化条件:无水乙醇为溶剂,n(SOCl2)∶n(2,5-二羟基苯甲酸)=1. 5∶1,回流条件下反应3 h,收率为93%。取代反应条件:K2CO3为碱,n(2-溴-1,1-二甲氧基乙烷)∶n(2,5-二羟基苯甲酸乙酯)=1. 3∶1,反应在丙酮溶剂中回流12 h,5-(2,2-二甲氧基乙氧基)-2-羟基苯甲酸乙酯最高收率为78%。傅克烷基化反应条件:甲苯为溶剂,n(PPA)∶n(5-(2,2-二甲氧基乙氧基)-2-羟基苯甲酸乙酯)=0. 5∶1,反应在80℃下进行2 h,收率为77%。水解条件:甲醇/水混合溶剂,n(Na OH)∶n(5-羟基苯丙呋喃-6-甲酸乙酯)=3∶1,50℃时反应4 h,收率为94%。 相似文献
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通过2-氨基-3-氰基噻吩与三氟乙酸、三氯氧磷反应"一锅法"制得2-三氟甲基-4-氯噻吩并[2,3-d]嘧啶,收率为60%,再与2-氨基-5-(取代苄硫基)-1,3,4-噻二唑发生芳香族亲核取代反应合成10个含噻二唑环噻吩并[2,3-d]嘧啶类含氟衍生物,收率为64%~75%。目标化合物的结构经红外光谱、核磁共振氢谱、质谱与元素分析表征,并采用MTT法对其进行初步的体外抗肿瘤活性筛选。结果表明,化合物Ⅳc和Ⅳf对Hep G2和BGC-823细胞的抑制活性高于对照样吉非替尼。 相似文献
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Razieh Mohebat Nasim Simin Afshin Yazdani-Elah-Abadi 《Polycyclic Aromatic Compounds》2019,39(2):148-158
p-Toluenesulfonic acid was applied as an efficient, non-toxic and solid acid catalyst for the one-pot, four-component condensation between 2-hydroxy-1,4-naphthoquinone, benzene-1,2-diamine, cyclic 1,3-dicarbonyl compounds and isatin or ninhydrin to afford the corresponding novel spiro[benzo[a]chromeno[2,3-c]phenazine] derivatives via a new two-step domino protocol under conventional heating and microwave irradiation. This solvent-free process produces biologically considerable heterocycles with the formation of five new bonds (two C–C, two C?N, and one C–O) and two new rings in a single operation and this effective green process provides considerable advantages such as: operational simplicity, very short reaction time, high yields, absence of any tedious process or purification, and it avoids hazardous reagents/solvents. 相似文献
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《Journal of Sulfur Chemistry》2013,34(6):605-615
Derivatives containing the cyclohepta4′,5′thieno[2′,3′:4,5]pyrimido[1,2-b][1,2,4,5]-tetrazin-6-one system were prepared from the reaction of 3-amino-2-thioxo-1,2,3,5,6,7,8,9-octahydro-4H-cyclohepta[4,5]thieno[2,3-d]pyrimidin-4-one (5) or its 2-methylthio derivative 6 with hydrazonoyl chlorides 9. The mechanism of the studied reactions has been discussed and the biological activity of the isolated products has been evaluated. 相似文献
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A series of novel thieno[2,3-b]pyridines were prepared from the reaction of the appropriate bromoacetylbenzofurans or bromoacetylbenzothiazole with the corresponding pyridinethione derivatives in ethanolic sodium ethoxide at reflux. Moreover, new bis(thieno[2,3-b]pyridine) derivatives have also been synthesized by the reaction of the appropriate bis-bromoacetyl derivatives with the corresponding pyridinethiones in the presence of sodium ethoxide. Attempts to synthesize the target bis(thieno[2,3-b]pyridine) derivatives by bis-alkylation of the corresponding (thieno[2,3-b]pyridin-2-yl)(hydroxyphenyl)methanone with the appropriate dihaloalkanes using a mild base were unsuccessful. 相似文献
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《Journal of Sulfur Chemistry》2013,34(6):630-636
A simple original approach to earlier unknown parent 2,7-dihydrothiopyrano[2,3-b]pyrrole (5) from allyl isothiocyanate and propargyl bromide via one-pot synthesis and thermal rearrangement of 2-(prop-2-ynylsulfanyl)-1H-pyrrole (4) has been developed. The compound 5 in the present study was successfully examined as 2,7-dihydrothiopyrano[2,3-b]pyrrole scaffold in the synthesis of corresponding N- and C-pyrrolecarbodithioates. 相似文献
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《Journal of Sulfur Chemistry》2013,34(6):595-603
Reaction of 5-(4-chlorophenyl)-2-thioxo-2,3-dihydro-1H-indeno[2',1':5,6] pyrido[2,3-d]pyrimidine-4,6-dione with hydrazonoyl chlorides gave 1,2,4-triazolo[4,3-a]pyrimidine derivatives regioselectively in good yields. The structures of the newly synthesized compounds are established on the basis of chemical and spectroscopic evidence as well as their synthesis by alternative methods. 相似文献
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以降冰片烯二酸酐为起始原料, 经水解中和和催化加氢制备了双环[2.2.1]-庚烷-2,3-二羧酸钠。通过研究催化加氢步骤中催化剂种类、催化剂用量、反应温度和反应压力等关键因素对双环[2.2.1]-庚烷-2,3-二羧酸钠的收率和纯度的影响, 获得了适宜的反应条件。实验结果表明:催化剂雷尼镍可代替文献报道的价格昂贵的钯/炭催化剂完成催化加氢反应, 在反应温度为60℃、反应压力为5MPa的条件下进行催化加氢, 双环[2.2.1]-庚烷-2,3-二羧酸钠的收率大于95%;红外光谱及核磁共振分析表明, 所得加氢产物与双环[2.2.1]-庚烷-2,3-二羧酸钠结构特征吻合。 相似文献
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《Journal of Sulfur Chemistry》2013,34(4-5):381-391
Pyridine-2(1H)-thione 1 reacted with phenyl isothiocyanate to give pyrido[2,3-d]pyrimidine derivative 3. Compound 3 reacted with halogen containing compounds 4a–d and methyl iodide in dimethylformamide/potassium hydroxide solution at room temperature to give 2,7-bisalkylthiopyrido[2,3-b]pyrimidine derivatives 5a–d and 9, respectively. Compounds 5a–d could be cyclized into thienopyrido[2,3-d]pyrimidine derivatives 6a–d by boiling with ethanolic potassium hydroxide solution. Compound 6a reacted with acetic anhydride or formic acid and gave the corresponding pyrimido[4″,5″:4′,5′]thieno[3′,2′:5,6]pyrido[2,3-d]pyrimidine derivatives 8a,b. Compound 9 reacted with hydrazine hydrate to yield pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidine derivative 11 which could be reacted with nitrous acid and dimethylformamide-dimethylacetal (DMF-DMA) and gave the final isolable products corresponding to the pyrazolo[4′,3′:5,6]pyrido[2,3-d]tetrazolo-[5,1-b]pyrimidine and pyrimido[1″,2″:1′,5′]pyrazolo[4′,3′:5,6]pyrido[2,3-d]1 2 4triazolo-[4,3-b] pyrimidine derivatives 13 and 17, respectively. Compound 11 also reacted with some β-dicarbonyl compounds such as acetylacetone (18) and ethyl acetoacetate (20) to yield the corresponding pyrimido[1″,2″:1′,5′]pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidine derivatives 19 and 21, respectively. Finally, compound 11 reacted with chloroacetyl chloride (22) to give the corresponding imidazo[1″′,2″′:1″,5″]pyrazolo[4″,3″:5′,6′]pyrido[3′,2′:5,6]pyrimido[2,1-c]1 2 4triazine derivative 23. 相似文献