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1.
Osamu Sugimoto 《Tetrahedron letters》2004,45(9):1915-1917
Magnesiation of functionalized aromatic halide, ethyl 3- or 4-iodobenzoate, was accomplished using active magnesium. The resulting phenylmagnesium iodides decomposed little by little in proportion to extension of the reaction time at room temperature. The magnesiation followed by addition of carbonyl compounds gave the corresponding adducts in good to moderate yields. 相似文献
2.
Treatment of N(3)-[(2-cyano-2-ethoxycarbonyl)vinyl]amino-N(4),N(4)-dimethylaminomethylenehydrazones of aromatic carbonyl compounds with hot acetic acid resulted in the formation of symmetrical gem-bis-(3-dimethylamino-1,2,4-triazol-1-yl)methanes, (3-dimethylamino-1,2,4-triazol-1-yl)arylmethyl acetates, and (3-dimethylamino-1,2,4-triazol-1-yl)alkenes of a gem-diaryl type depending upon whether the carbonyl compound was aldehyde or ketone. 相似文献
3.
Roman Gancarz Irena Gancarz Agnieszka Masiowska 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract In the reaction mixture of carbonyl compound, amine and diethyl phosphite several different reactions are observed. The formation of aminophosphonate (Kabachnik- Fields reaction) is frequently accompanied with the formation of hydroxyphosphonate (Pudovik reaction) or product of its rearrangement. 1–3 This is due to the presence of one electrophile (carbonyl compound) and two nucleophiles (amine and phosphite) in the reaction mixture, which may compete for the electrophilic center. 相似文献
4.
Blair VL Clegg W Kennedy AR Livingstone Z Russo L Hevia E 《Angewandte Chemie (International ed. in English)》2011,50(42):9857-9860
Ligand domin(o)ated: In contrast to the straightforward deprotonation of benzothiazole using Grignard reagents, treatment of benzothiazole with 1 leads to a novel type of activation. The initial magnesiation initiates an unstoppable domino reaction of C?C coupling, ring opening, nucleophilic addition, and deprotonation to give 2. THF=tetrahydrofuran. 相似文献
5.
二氯卡宾与四苯基环戊二烯酮反应机理的研究 总被引:4,自引:1,他引:4
二氯卡宾与四苯基环戊二烯酮(1)反应放出CO,并生成偕二卤化物(3)、二氯环氧乙烯(4)以及双键加成物(5)。羰基叶立德的芳香性结构及其“中介型”爸象决定了该应以脱CO为主电环化途径次之。 相似文献
6.
Efficient ruthenium‐, rhodium‐, palladium‐, copper‐ and iridium‐catalysed methodologies have been recently developed for the synthesis of quinolines by the reaction of 2‐aminobenzyl alcohols with carbonyl compounds (aldehydes and ketones) or the related alcohols. The reaction is assumed to proceed via a sequence involving initial metal‐catalysed oxidation of 2‐aminobenzyl alcohols to the related 2‐aminobenzaldehydes, followed by cross aldol reaction with a carbonyl compound under basic conditions to afford α,β‐unsaturated carbonyl compounds. These aldehydes or ketones can be also generated in situ via dehydrogenation of the related primary and secondary alcohols. In the final step cyclodehydration of the α,β‐unsaturated carbonyl compound intermediates gives quinolines. Good yields of quinolines were also obtained by reacting 2‐nitrobenzyl alcohols and secondary alcohols in the presence of a ruthenium catalyst. Finally, aniline derivatives afforded also a useful access to quinolines by the reaction with 1,3‐propanediol or 3‐amino‐1‐propanol, or in a three‐component reaction with benzyl alcohol and aliphatic alcohols. 相似文献
7.
A triphenylphosphine-catalyzed cyclization of alpha-keto esters, alpha-keto nitriles, or alpha,alpha,alpha-trifluoroacetophenone with dimethyl acetylenedicarboxylate is reported to produce highly functionalized alpha,beta-unsaturated gamma-butyrolactones in moderate yields. Thus treating a mixture of methyl 4-nitrophenylglyoxylate and dimethyl acetylenedicarboxylate with 20 mol % of triphenylphosphine afforded 5,5'-disubstituted 3-methoxy-4-(methoxycarbonyl)-2(3H)-furanone in 94% yield. In the reaction of alpha-keto esters R(1)COCOOMe, an electron-withdrawing R(1) substituent is required for satisfactory reactivity. On the other hand, electron-donating R(1) substituents give higher yields with alpha-keto nitriles R(1)COCN. Another electron-deficient carbonyl compound, alpha,alpha,alpha-trifluoroacetophenone, gave the corresponding lactone in good yield. The use of an alpha-hydroxy ketone as an electrophilic carbonyl compound with more than 1 equiv of triphenylphosphine produced dihydrofuran derivatives. One equivalent of triphenylphosphine oxide was obtained as a major product. An intramolecular Wittig reaction is proposed as a reaction mechanism. 相似文献
8.
A novel thermosetting imide compound having a respective phenylethynyl carbonyl group at both terminal ends was newly synthesized from an acid anhydride having a phenylethynyl carbonyl group and various diamine compounds. The thermosetting behavior of the obtained novel thermosetting imide compound having phenylethynyl carbonyl groups was analyzed through differential scanning calorimetry measurements and infrared spectroscopic analysis. As a result, it became clear that a curing reaction of phenylethynyl carbonyl groups proceeds at approximately 200°C and that the curing reaction thereof proceeds at a temperature that is lower by 150°C or more compared with that of phenylethynyl groups. Examination of the polymerization reaction of the imide compounds having phenylethynyl carbonyl groups using model compounds revealed that a reaction that imparted an alkene C=C and polycyclic aromatic structure progressed. Moreover, a network polymer obtained from a thermosetting imide compound having respective phenylethynyl carbonyl groups at both terminal ends exhibited extremely superior heat resistance and thermal decomposition resistance. These superior thermal properties are thought to be due to the strong molecular interaction (molecular packing) that results from the polycyclic aromatic structures and alkenes produced through polymerization of the phenylethynyl carbonyl groups and to the suppression of the movement of the molecular chains. 相似文献
9.
Yun-Yun Yang 《Tetrahedron》2006,62(43):10079-10086
A Zn(OTf)2-catalyzed cascade reaction of anilines with aromatic aldehydes and carbonyl compounds was described. This one-pot three-component reaction afforded the corresponding β-amino carbonyl compounds, β-amino esters, and β-amino ketones in good to excellent yields. The reaction was also applied for the liquid-phase synthesis of β-amino carbonyl compound library using PEG as a support. 相似文献
10.
Selective, direct ortho magnesiation of (S)-2,2'-bis(isopropoxycarbonyl)-1,1'-binaphthyl (6) has been achieved under mild conditions, using magnesium bis(2,2,6,6-tetramethylpiperamide) [Mg(TMP)(2)]. In combination with the subsequent reaction with the appropriate electrophiles, bromine and iodine, this method constitutes a key step in establishing a new and concise synthetic route to a wide variety of N-spiro C(2)-symmetric chiral quaternary ammonium bromides of type 1. 相似文献
11.
Herance JR Ferrer B Bourdelande JL Marquet J Garcia H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(14):3890-3895
A photocatalytic system to effect the Meerwein-Ponndorf-Verley reduction of carbonylic compounds to alcohols has been developed. The system comprises [Ru(bpy)3]2+ as a photosensitizer, triethanolamine as a sacrificial electron donor, viologen as an electron acceptor, and the carbonyl compound and iPrOH as Meerwein-Ponndorf-Verley reagents. The photocatalytic reaction can be performed in neat iPrOH or in 1-butyl-3-methylimidazolium ionic liquid. Mass spectrometric detection of the viologen hydride derivative VH+ confirms that this species is the reducing agent responsible for the carbonyl compound reduction. The reaction intermediates involved in the photocatalytic system have also been characterized by laser flash photolysis. 相似文献
12.
<正> 芳香卤代物芳环上的卤原子在光诱导或电引发下可通过自由基链式亲核取代反应(S_(RN)|)而被有机负离子所取代。 我们以3-溴苯基-苯基-甲酮为底物,在丙腈碳负离子存在下进行光照,结果芳酮环上的溴原子未发生 S_(RN)|取代,而是在羰基上发生了光诱导加成反应,生成了未见文献报道的新化合物1-苯基-1-(3-溴苯基)-2-氰基丙醇-1(I) 相似文献
13.
Synthesis of nitrogen-containing heterocycles. 4. A facile route to new 1, 2, 4-triazole derivatives
The reaction of amino-N(4),N(4)-dimethylaminornethylenehydrazones 1 of some aliphatic carbonyl compounds with ethyl ethoxymethylenecyanoacetate 2 gave directly symmetrical gem-bis(3-dimethylamino-1, 2, 4-triazol-1-yl)alkanes 4 and (3-dimethylamino-1, 2, 4-triazol-1-yl)alkenes 5 at room temperature, with the former being major product. On the other hand, the reaction of amino- N (4)-methylaminomethylenehydrazone homologue 1 of aliphatic ketone with 2 gave ethyl 2-alkyl-5-methylamino[1, 2, 4]triazolo[1, 5-c]pyrimidine-8-carboxylate 7 as the only product with elimination of alkane. 相似文献
14.
An optically active, axially chiral NAD model compound(1) with a quinoline ring system was reduced by the chiral NADH model compound (4), affording a mixture of 1,2- and 1,4-dihydroquinolines. The carbonyl orientation governs the molecular arrangement in the transition state of the reaction and determines the regio- and enantioselectivity of the product. 相似文献
15.
2-氨基-4H-咪唑啉-4-酮衍生物的快速平行合成法 总被引:3,自引:0,他引:3
咪唑啉酮衍生物是一类具有良好生物活性和药理活性的杂环化合物 [1,2 ] ,尤其是一些 2 -氨基咪唑啉酮表现出良好的杀菌、抗炎及抗癌活性 [3 ,4 ] .从自然界如一些海洋生物中可分离得到含 2 -氨基咪唑啉酮结构的生物碱 [5,6] .最近 ,组合化学方法广泛地应用于有机合成 ,它包括固相合成法和液相合成法[7~ 9] .我们曾应用氮杂 Wittig反应制得 2 -氨基取代咪唑啉酮衍生物 ,部分化合物表现出一定的抑菌活性 [10 ,11] .本文进一步报道应用液相平行反应法快速合成 2 -氨基 - 4H-咪唑啉 - 4-酮衍生物 (4) .该方法应用烯基膦亚胺 1与苯基异氰酸酯的… 相似文献
16.
Inorganic cathodes of rechargeable Mg batteries suffer from limited selections, while organic materials provide more options. Herein, three conjugated dianhydrides, pyromellitic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride and 3,4,9,10-perylenetetracarboxylic dianhydride are comparatively investigated to elucidate the effects of conjugated structure on the Mg2+ storage performances. It is observed that the reversible Mg2+ storage capacity is more dependent on the conjugated structure than carbonyl numbers. Ex-situ mechanism study illustrates that the extended conjugated structure delocalizes the electron density, hence enhancing carbonyl enolization and increasing the Mg2+ storage capacity. Furthermore, the largely conjugated structure buffers the charge density change during repeated magnesiation/demagnesiation resulting in better cyclability. Prominently, 3,4,9,10-perylenetetracarboxylic dianhydride shows a high Mg2+ storage capacity (160 mAh g−1) and a good cycling stability (80 % capacity retention after 100 cycles) with the largest conjugated structure. This work provides a low-cost cathode for rechargeable Mg batteries that can be utilized for designing high-performance organic Mg battery cathodes. 相似文献
17.
SHI Wei-Feng JIANG Nan WANG Jian-Bo 《有机化学》2003,23(Z1):17-17
In the process of preparing α-diazo carbonyl compound 2 by imidation of 1, we unexpectedly observed a direct conversion of the hydroxyl group into trichloroacetylamino group. In this presentation, we report this unprecedented reaction, as well as the Rh2(OAc)4-catalyzed reaction of the resulting β-(trichloroacetyl)amino β-diazo carbonylcompounds 3. [ 1] 相似文献
18.
A wide range of highly functionalized indoles were prepared by the successive magnesiation of readily available o-alkynyl protected anilines using TMPMgCl.LiCl or LDA, followed by a KH-mediated cyclization reaction. 相似文献
19.
A wide range of polyfunctionalized quinolines was prepared via chemo- and regioselective magnesiation reactions using appropriate Mg reagents, such as i-PrMgCl.LiCl, MesMgBr.LiCl, Mes2Mg.2LiBr, TMPMgCl.LiCl, and TMP2Mg.2LiCl. An application to the total synthesis of the biologically active compound talnetant was performed (six steps, 28%). 相似文献
20.
Saito S Nagahara T Shiozawa M Nakadai M Yamamoto H 《Journal of the American Chemical Society》2003,125(20):6200-6210
Various alpha,beta-unsaturated carbonyl compounds were coordinated with aluminum tris(2,6-diphenylphenoxide) (ATPH) to give the corresponding Lewis acid-base complexes in a distinctive coordination fashion (selective coordination). ATPH recognizes carbonyl substrates and subsequently orients itself as it forms a stable complex through selective coordination with the carbonyl oxygen. Selective coordination also confers a conformational preference to each carbonyl compound under the steric and electronic influence of ATPH, which enables the vinylogous aldol reaction of alpha,beta-unsaturated carbonyl compounds to give the corresponding gamma-aldol products with different regio- and stereoselectivities. 相似文献