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合成了γ-氨丙基七甲基环四硅型氧烷和γ-氨丙基甲基二乙氧基硅烷。研究了它们与八甲基环四硅氧烷在阳离子乳化剂及阴离子型乳化剂存在下的乳液共聚合反应。探讨了催化剂量、单体浓度、氨丙基含量及温度等对聚合的影响。 相似文献
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采用农药厂副产物三乙基-3-苯氧基苄基氯化铵与4-氯苯基环丙基酮肟在碱性的条件下反应合成4-氯苯基环丙基酮厉-O-(3-苯氧基苄基)醚,产率80%。 相似文献
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4—氯苯基环丙基酮肟—O—(3—苯氧基苄基)醚的新合成途径 总被引:1,自引:0,他引:1
采用农药厂副产物三乙基-3-苯氧基苄基氧化铵与4-氯苯基环丙基酮肟在碱性的条件下反应合成4-氯苯基环丙基酮肟-O-(3-苯氧基苄基)醚,产率80%。 相似文献
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采用3-(4-三氟甲基苯亚甲基)吲哚啉-2-酮和2-(4-三氟甲基苯亚甲基)-1H-茚-1,3(2H)-二酮分别与鉮盐在二氯甲烷中,碳酸钾或氟化钾存在下反应,可高产率、高立体选择性地得到以反式构型为主的含三氟甲基的3'-螺环丙基取代的氧化吲哚和2'-螺环丙基取代的茚二酮衍生物.产物相对构型经X射线单晶衍射或1H-1H NOESY谱确定.还从反应机理的角度对产物构型做了解释. 相似文献
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西地那非的合成 总被引:2,自引:0,他引:2
西地那非 (sildenafil,商品名 :Viagna)是美国辉瑞公司于 1 997年开发上市的新型磷酸二酯酶 5型(PDE5 )抑制剂 ,化学名为 5 〔2 乙氧基 5 (4 甲基哌嗪 1 磺酰基 )苯基〕 1 甲基 3 正丙基 1 ,6 二氢 7H 吡唑并〔4,3 d〕嘧啶 7 酮。作者对文献[1- 3] 的合成路线及合成方法进行了改进 :在中间体 4 氨基 1 甲基 3 正丙基吡唑 5 甲酰胺制备中 ,采用水合肼作还原剂 ,收率达 91 5 % ,且后处理方便 ,易于操作 ,安全简单 ,产品质量稳定。HNMR谱 ,元素分析结果与对照品完全一致。在环合反应中使用表面活性剂十二… 相似文献
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A novel facile synthesis of substituted and functionalized allylsilane has been developed. This essentially one-pot procedure involves (1) (dimethylphenylsilyl)methyl cerium chloride addition to cyclopropyl ketone and (2) MgI(2) etherate-mediated Julia homoallylic transposition of the corresponding cyclopropyl carbinol. The bifunctional homoiodo allylsilanes, readily accessible by this method, would be useful and versatile synthons in organic synthesis. [reaction: see text] 相似文献
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Infrared spectra in the vapour, liquid, and crystalline states and Raman spectra in the liquid and crystalline states have been obtained for cyclopropyl methyl ketone and for methyl cyclopropylcarboxylate. In cyclopropyl methyl ketone, the dominant conformer in the liquid and vapour states, the cis, has been shown to exist exclusively in the crystal. In methyl cyclopropylcarboxylate, the conformer dominant in the liquid and vapour states has been demonstrated to exist in the crystal. Vibrational assignments are made for the ring modes and for those modes which are sensitive to conformational changes. 相似文献
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Conformations of cyclopropyl methyl ketone have been studied using ab initio methods in an effort to quantify the effects of conjugative overlap between the cyclopropane ring and an adjacent ketone carbonyl. Results were comparable with previous experimental and theoretical studies. Cyclopropyl methyl ketone exhibits a global energy minimum in the s-cis conformer and a local energy minimum near the s-trans conformer. The potential energy curve obtained was used to derive torsion parameters which were employed in molecular mechanics studies of the conformations of the set of bicyclo[m.1.0]alkan-2-ones having larger ring sizes from five- to 16-membered. Similar conformations for the cyclopropyl ketone substructure are observed for all the medium and large ring systems examined. Possible synthetic ramifications of local conformational anchoring by this functional group array are discussed. 相似文献
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Mitsunori Honda Kenta NakaeToshiaki Nishizawa Mitsuhiro SudaKo-Ki Kunimoto Masahito Segi 《Tetrahedron》2011,67(49):9500-9508
The reaction of silylcyclopropyl bromides with dichloromethyl methyl ether in the presence of n-butyllithium is investigated. Under basic reaction conditions, the corresponding cyclopropylidene derivatives are exclusively obtained. The resulting cyclopropylidene compounds are subjected to protonolysis or trapping with electrophiles in a one-pot to give the cyclopropyl silyl ketone derivatives in good yields. Acidic treatment of derived cyclopropyl silyl ketone allows isomerization to give the thermodynamically favorable trans form exclusively. 相似文献
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Eleven structurally different α, β-unsaturated ketones were subjected to the Clemmensen reduction under anhydrous conditions using amalgamated zinc, hydrogen chloride in a solution of ethyl ether, and acetic anhydride. In all cases but one the formation of cyclopropyl acetates was observed. 4-Methyl-3-penten-2-one, methyl vinyl ketone, 2-isopropylidene-1-cyclopentanone, and 2-cyclohepten-1-one led to substituted cyclopropyl acetates. Stereospecific reactions were found with 2-ethylidene-1-cyclopentanone, 2-benzylidene-1-cyclohexanone, and methyl 1-cyclohexenyl ketone, whereas 3-penten-2-one, 3-methyl-3-buten-2-one, and 2-methyl-2-cyclohexen-1-one afforded mixtures of the isomeric cyclopropyl acetates. These results are interpreted in terms of the intital formation of an allylic anion which undergoes electrocyclic closure. A stereospecific course is followed when geometric constraints permitted. Exceptions are discussed. 相似文献
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The reaction of 1-silylcyclopropyl anions with dichloromethyl methyl ether is described. The reaction with an excess amount of dichloromethyl methyl ether gives the corresponding cyclopropyl silyl ketones in low yields. On the other hand, the reaction under basic conditions proceeded smoothly to afford the corresponding cyclopropylidene derivatives, exclusively. The resulting cyclopropylidene compounds are subjected to hydrolysis or trapping with electrophiles easily to give the cyclopropyl silyl ketone derivatives in good yields. 相似文献
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Controlled thermal decomposition of the sodium salt of cyclopropyl methyl ketone tosylhydrazone gives 1-methylcyclobutene of excellent purity in good yield. 相似文献
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Dr. Simon Wübbolt Dr. Choon Boon Cheong Dr. James R. Frost Dr. Kirsten E. Christensen Prof. Dr. Timothy J. Donohoe 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11435-11440
A vinyl cyclopropane rearrangement embedded in an iridium-catalyzed hydrogen borrowing reaction enabled the formation of substituted stereo-defined cyclopentanes from Ph* methyl ketone and cyclopropyl alcohols. Mechanistic studies provide evidence for the ring-expansion reaction being the result of a cascade based on oxidation of the cyclopropyl alcohols, followed by aldol condensation with the pentamethyl phenyl-substituted ketone to form an enone containing the vinyl cyclopropane. Subsequent single electron transfer (SET) to this system initiates a rearrangement, and the catalytic cycle is completed by reduction of the new enone. This process allows for the efficient formation of diversely substituted cyclopentanes as well as the construction of complex bicyclic carbon skeletons containing up to four contiguous stereocentres, all with high diastereoselectivity. 相似文献
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Simon Wübbolt Choon Boon Cheong James R. Frost Kirsten E. Christensen Timothy J. Donohoe 《Angewandte Chemie (International ed. in English)》2020,59(28):11339-11344
A vinyl cyclopropane rearrangement embedded in an iridium‐catalyzed hydrogen borrowing reaction enabled the formation of substituted stereo‐defined cyclopentanes from Ph* methyl ketone and cyclopropyl alcohols. Mechanistic studies provide evidence for the ring‐expansion reaction being the result of a cascade based on oxidation of the cyclopropyl alcohols, followed by aldol condensation with the pentamethyl phenyl‐substituted ketone to form an enone containing the vinyl cyclopropane. Subsequent single electron transfer (SET) to this system initiates a rearrangement, and the catalytic cycle is completed by reduction of the new enone. This process allows for the efficient formation of diversely substituted cyclopentanes as well as the construction of complex bicyclic carbon skeletons containing up to four contiguous stereocentres, all with high diastereoselectivity. 相似文献
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《Tetrahedron letters》1988,29(33):4151-4152
Lewis acid assisted solvolysis of the cyclopropyl ketone 5 offers a simple method to introduce the C-7 OH group in anthracyclinones, leading to a formal total synthesis of (+)-daunomycinone. 相似文献