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使用廉价易得的邻烯基甲酰苯胺在可见光的诱导下发生自由基环化反应, 以良好至优秀的产率合成了15种2-喹啉酮衍生物. 该方法简单高效、 条件温和、 产率较高, 具有优异的官能团兼容性, 不仅拓展了邻烯基甲酰苯胺参与的新型有机反应, 也为光催化合成喹啉酮类化合物提供了一条新途径. 相似文献
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在K2CO3作为碱、乙腈作为溶剂的条件下,将2-氯甲基-4-苯基喹啉-3-羧酸乙酯(3)分别与5,7-二氯-8-羟基喹啉(4a)和5,7-二溴-8-羟基喹啉(4b)发生Williamson反应,以高收率得到结构新颖的二氯或二溴取代的双喹啉类目标化合物2-(5,7-二氯/二溴-8-喹啉氧甲基)-4-苯基喹啉-3-羧酸乙酯(2a,2b);其结构经波谱数据和元素分析证实. 相似文献
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《高等学校化学学报》2015,(9)
以Brnsted酸性离子液体1-乙基-3-丁基咪唑对甲苯磺酸盐为催化剂,将芳香醛和2-甲基喹啉类化合物在无溶剂或甲苯中于120℃反应48 h,制备了一系列的1,3-二(2-喹啉基)丙烷化合物,产率56%~92%,产物结构经核磁共振波谱和高分辨质谱确证.该方法具有简便易行、产率较高等特点. 相似文献
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In the presence of titanium(IV) tetraethoxide ((EtO)4Ti), menthyl arylglyoxylates are prepared by transesterification of ethyl arylglyoxylates and natural (−)‐(1R,2S,5R)‐menthol. Using menthyl as a chiral auxiliary, the corresponding novel (R)‐menthyl 2‐aryl‐2‐hydroxybutanoates are synthesized by the addition of Et2Zn with menthyl arylglyoxylates. The structures of the products are characterized by IR and 1H‐ and 13C‐NMR spectroscopy, mass spectrometry, and elemental analysis. The diastereoselectivities are analyzed by HPLC. The addition reactions are completed with good yields and high diastereoisomeric excess (de up to 95%), and, after hydrolysis, the (R)‐2‐aryl‐2‐hydroxybutanoic acids are obtained with high optical purities. 相似文献
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The reactions of 2-nitro-5,10,15,20-tetraphenylporphyrin (1) and its Ni (Ⅱ) (2), Cu (Ⅱ) (3), Zn (Ⅱ) (4) complexes with sodium 2-naphthoxide have been investigated in different solvents for preparing 2-substituted porphyrins. 2-(2-Hydroxynaphthyl)-5,10,15,20-tetraphenyl porphyrin (5) and its Ni (Ⅱ) (6), Cu (Ⅱ) (7), Zn (Ⅱ) (8) complexes were obtained in 72%, 78%, 81% and 65% yields in 2-naphthol at 150 ℃ respectively. The same products were also obtained in other protic solvents such as diglycol and diglycol monomethyl ether. When the reactions proceeded in aprotic solvent DMF at 150 ℃, besides 5 (70%), 6 (34%), 7 (54%) and 8 (50%), the corresponding 2-(2-naphythoxy)-5, 10,15,20-tetraphenylporphyrin (9), and its Ni (Ⅱ) (10), Cu (Ⅱ) (11), Zn (Ⅱ) (12) complexes were also obtained in minor, 40%, 18% and 2% yields respectively, but only 5, 6, 7, 8 were found at room temperature in DMF or DMSO. These reactions axe much faster than those of 1-4 with sodium phenoxide. The formation of C-coupling products 5-8 was proposed via SRN 1 mechanism. 相似文献
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Treatment of lithio derivativ
e of novel PEG-supported a-phenylselenopropionate with aldehydes, followed by oxidation-elimination with 30% hydrogen peroxide, formed Baylis-Hillman products, which were then reacted with sodium arylsulfinate. The resulting sulfonylated products were cleaved from the PEG efficiently affording methyl (2Z)-2-arylsulfonylmethyl-2-alkenoates in good yields and high purities. 相似文献
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The reactivity of 1,1‐diethoxy‐3‐(1,3‐dithian‐2‐yl)propan‐2‐one, a diacetal of oxobutanedial, and some of its derivatives toward selected reagents has been studied. As expected, hydride and Grignard‐type additions take place at the oxo moiety only and give the corresponding alcohols in good‐to‐excellent yields. Standard reductive amination occurs at the oxo moiety as well, but the reaction was in most cases not selective and furnished the expected amine mixed with 3‐(1,3‐dithian‐2‐yl)‐1,1‐diethoxypropan‐2‐ol. The conversion of the diethyl acetal moiety to an aldehyde group is generally an efficient transformation, but some aldehydes are unstable, making the deprotection useless. If the acetal contains a tertiary alcohol or a benzyloxy moiety, however, stable products are formed in good yields. Attempts to convert the 1,3‐dithiane substituent into an aldehyde group without concomitant decomposition of the product were totally unsuccessful. The chemical potential of this moiety, therefore, has to be utilized at an earlier stage and under different conditions. 相似文献
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Synthesis of 1‐Acyl‐3,4‐dihydroquinazoline‐2(1H)‐thiones by Cyclization of N‐[2‐(Isothiocyanatomethyl)phenyl] Amides Generated in situ from N‐[2‐(Azidomethyl)phenyl] Amides
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An efficient method for the preparation of 1‐acyl‐3,4‐dihydroquinazoline‐2(1H)‐thiones 5 has been developed. The reaction of N‐[2‐(azidomethyl)phenyl] amides 3 , easily prepared by a three‐step sequence starting with (2‐aminophenyl)methanols, with Ph3P, followed by CS2, allowed generation of N‐[2‐(isothiocyanatomethyl)phenyl]‐amide intermediates 4 , which underwent cyclization on treatment with NaH to furnish the corresponding desired products in generally good yields. 相似文献
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Unexpectedly, in the reaction of 2‐bromo‐2‐phenylacetonitrile derivatives with 2 mol‐equiv. of benzothioamide in DMSO, 3,5‐diaryl‐1,2,4‐thiadiazoles were obtained in excellent yields (83–90%) and in short reaction times (5–10 min). It is found that, in DMF, a quite different reaction takes place and 2,5‐diaryl‐1,3‐thiazol‐4‐amines are formed as the main products. 相似文献
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M. M. El-Dessouky F. Abdel-Rehim A. -A. Abdel-Azim I. Gar-Alm Rashed 《Journal of Radioanalytical and Nuclear Chemistry》1988,125(2):485-492
Gamma radiolysis of 2-acetylfuran (AF) in 2-propanol, in absence of atmospheric oxygen, has been investigated. The radiation yields of hydrogen, methane at different doses as well as radiolytic products in solution were determined. The radiolytic products were determined by gas chromatography coupled with mass spectrometry. The mechanisms for formation of detected radiolytic products and the effect of (AF) concentration on hydrogen and methane yields are discussed. 相似文献
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建立了在水相介质中, 在碳酸钾/硫脲联合促进下, 具有邻位氨基溴的酯和邻位氨基溴的酮在室温下发生溴化氢消除反应, 高收率地制备α,β-脱氢氨(功能化烯胺)的新方法. 共考察了23种不同结构α,β-邻位氨基溴的酯和α,β-邻位氨基溴的酮的反应情况, 证明该方法具有广泛的适应性. 实验发现, 无论底物为α-氨基-β-溴结构还是α-溴-β-氨基结构, 反应过程中都要经过一个氮丙啶过程, 而氮丙啶的开环是区域专一的, 因此产物具有区域专一性(烯键上的氨基均处在羰基的α-位). 所有产物的结构均经过核磁共振波谱及高分辩率质谱确证. 克量级放大实验结果表明, 该方法具有一定的用于工业化生产的可行性. 相似文献
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Biswanath Das Cheruku Ravindra Reddy Chava Sindhu Duddukuri Nandan Kumar Martha Krishnaiah 《Helvetica chimica acta》2011,94(2):289-292
[(Tosylamino)alkyl]naphthalenols have efficiently been synthesized by nucleophilic addition of naphthalen‐2‐ol with N‐tosyl imines (derived from both aromatic and aliphatic aldehydes) in the presence of BF3?OEt2 as a catalyst at room temperature. The products are formed within 5–9 h in high yields (72–91%). 相似文献
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在甲苯中,以ZnBr_2为催化剂、4-二甲氨基吡啶为碱,通过N-Boc取代的炔基胺类化合物的环化反应合成了5位取代的2-噁唑烷酮类化合物。考察了催化剂种类、碱、温度等对反应的影响,在优化条件下以良好的产率得到了一系列目标产物。 相似文献