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1.
Potassium beta-aminoethyltrifluoroborates were prepared in good yields via hydroboration of the corresponding enecarbamates using the Snieckus hydroborating reagent. A wide variety of phenethylamines containing a potentially free primary amine after appropriate deprotection have been successfully prepared in good yield using these organotrifluoroborates as partners in Suzuki-Miyaura coupling with aryl bromides, iodides, and triflates. 相似文献
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Marina V. Chirskaya Natalia L. Sergovskaya Sergey I. Sviridov 《Tetrahedron letters》2004,45(48):8811-8813
Substituted 3-bromotetrahydrofurans were prepared from homoallylic alcohols via bromination and cyclization in methanol in the presence of potassium carbonate. 相似文献
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A library of benzimidazole-substituted potassium organotrifluoroborates was prepared via the condensation of various potassium formyl-substituted aryl- and heteroaryltrifluoroborates with aromatic 1,2-diamines under oxidative conditions. The efficient Suzuki-Miyaura cross-coupling of products thus formed to various aryl and heteroaryl bromides was achieved in good yields. The method allows the facile preparation of benzimidazole-containing triaromatic products in two steps from simple potassium formyl substituted aryl- or heteroaryltrifluoroborates. 相似文献
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[reaction: see text] Potassium bromo- and iodomethyltrifluoroborates have been prepared via in situ reaction of n-BuLi with dibromo- and diiodomethane, respectively, in the presence of trialkyl borates, followed by treatment with KHF(2). Moreover, a new synthetic method for the preparation of potassium organotrifluoroborates through nucleophilic substitution of the halide in these potassium halomethyltrifluoroborates is described. 相似文献
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Zbigniew J. Witczak 《Tetrahedron》1985,41(21):4781-4785
A new class of selenosugars—glycosyl isoselenocyanates—has been prepared via reaction of the corresponding glycosyl isocyanides with elemental Se under the catalytic influence of triethylamine. 2,3,4,5,6-Penta-O-acetyl-D-gluconyl isoselenocyanate was also prepared in moderate yield by reaction of 2,3,4,5,6-penta-O-acetyl-D-gluconyl chloride with potassium selenocyanate in anhydrous acetone. The isoselenocyanate structure is ascertained by physical (13C-NMR, IR) and chemical methods—formation of selenoureas, and radical induced fragmentation by reaction with tri-n-butyltin hydride via intermediate isocyanide, to 1,5-anhydro-D-hexitols. 相似文献
6.
[reaction: see text] 2-BF3-substituted 1,3-butadienes with potassium and tetrabutylammonium counterions have been prepared in gram quantities from chloroprene via a simple synthetic procedure. The potassium salt of this new main group element substituted diene has been characterized by 1H, 13C, 11B, and 19F NMR. Diels-Alder reactions of these dienes with ethyl acrylate and methyl vinyl ketone are reported, as well as subsequent Pd-catalyzed cross-coupling reactions of those Diels-Alder adducts. 相似文献
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Roland Verhé Norbert De Kimpe Laurent De Buyck Marc Tilley Niceas Schamp 《Tetrahedron》1980,36(1):131-142
Reaction of N-1(2,2-dichloroalkylidene)amines, prepared by chlorination of aliphatic aldimines with N-chlorosuccinimide, with excess of potassium cyanide in methanol gave β-chloro-α-cyanoenamines. When the reaction was carried out for a longer period, α-chloroimidates were isolated (except for N-t-Bu compounds). Reaction of the α-chloroaldimines with potassium cyanide in dimethylsulphoxide at 70° gave 1,2-dicyanoenamines while at 120° 2-amino-5-cyanopyrrols were produced via 1,3-dicyanoenamines. The reaction mechanisms are discused. 相似文献
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A wide variety of alkoxymethyltrifluoroborate substrates were prepared via SN2 displacement of potassium bromomethyltrifluoroborate with various alkoxides in excellent yields. These alkoxymethyltrifluoroborates were effectively cross-coupled with several aryl chlorides. This method provides a unique dissonant disconnect that allows greater flexibility in the design of new and improved synthetic pathways. 相似文献
10.
Bisphosphine compounds have a wide range of applications. In this paper, we reported that bisphosphine compounds could be prepared in moderate to good yields from dialkyl acylphosphonates under mild conditions in the presence of phenyldioxaborolane and potassium hydroxide via a C-P bond cleavage and a subsequent 1,2-migration of phosphoryl group. 相似文献
11.
Yi‐Zhong Zhu 《合成通讯》2013,43(19):3359-3366
Aryl nitriles have been prepared from the corresponding aryl halides with potassium hexacyanoferrate(II) using Pd/C as a catalyst. No ligand or cocatalyst is required. This protocol also avoids the use of highly toxic alkali cyanides. Furthermore, the catalyst can be recycled via simple filtration and washing sequences. 相似文献
12.
A series of 1,2,4-diazaphospholide (dp(-)) samarium complexes with a variety of coordination modes were prepared via the metathesis reaction of SmCl3(THF)3 and potassium 3,5-disubstituted 1,2,4-diazaphospholide or by the reaction of Sm[N(SiMe3)2]3 and 3,5-diphenyl-1,2,4-diazaphosphole. 相似文献
13.
Zheng Li Jin-Lan Yu Sheng-Yi Shi Wei Zhu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1031-1037
A rapid method to N-acyl ureas from corresponding N-acyl thioureas is described. N-coumaroyl-N′-arylthioureas, which are easily prepared by the reaction of coumarin-3-carboxylic acid chloride with potassium thiocyanate and arylamines, can be expeditiously transformed into corresponding N-acyl ureas via r.t. grinding with wet silica supported potassium permanganate under solvent-free conditions in an excellent yield. 相似文献
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Mingzhong Cai Yizheng Huang Rongli Zhang 《Journal of organometallic chemistry》2004,689(15):2436-2440
A silica-supported poly-γ-diphenylarsinopropylsiloxane palladium(0) complex has been prepared from γ-chloropropyltriethoxysilane via immobilization on fumed silica, followed by reacting with potassium diphenylarsenide and palladium chloride, and then the reduction with hydrazine hydrate. The palladium(0) complex has been found to catalyze the allylation of aldehydes via the formation of π-allylpalladium complexes, using allylic chlorides as allylating agent and SnCl2 as reducing agent. This polymeric palladium complex can be recovered and reused. 相似文献
16.
二氧化硅-聚硅氧烷负载硫杂-15-冠-5铂、铑配合物的合成及其催化硅氧化性能 总被引:1,自引:0,他引:1
6-(ω'-十一碳烯氧甲基)-1-硫杂-4,7,1O,13-四氧杂环十五烷与三乙氧基硅烷进行硅氢加成,产物依次以气相法二氧化硅固载、氯亚铂酸钾或三氯化铑络合,合成了相应的二氧化硅-聚硅氧烷负载硫杂-15-冠-5-铂、铑配合物,并研究了它们在烯烃与三乙氧基硅烷的硅氢加成反应中的催化性能.结果表明,二者均为硅氢加成反应的高效催化剂. 相似文献
17.
The new rhenium(I) bipyridine crown ether receptors 1-4 have been prepared and their ion pair recognition properties examined. The crystal structure of [1.KCl](2).2H(2)O demonstrates that potassium is coordinated by benzo-18-crown-6 and chloride is hydrogen bonded to the amide groups. Receptor 3 extracts solid KCl and KOAc into chloroform via ion pair complexation. NMR and emission titration studies with receptors 1-4 and KCl/KOAc show that cobound potassium enhances anion binding strength by electrostatic and conformational effects. Significant cooperative interactions are observed between the anion and cation sites for host 4 in CH(3)CN. This molecule coordinates potassium to form a 1:1 intramolecular sandwich complex, which preorganizes the host for acetate binding. 相似文献
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Powdered samples of complex oxides-potassium niobates with a layered structure were prepared via high-temperature synthesis followed by grinding. The action spectra of photoinduced processes on potassium niobates with different phase compositions in aqueous and aquo-organic systems were determined. It was shown that the evolution of oxygen was due to its photodesorption and occurred upon illumination with light at an energy near the edge of intrinsic niobate absorption. The formation of hydrogen in aqueous systems is due to the photocatalytic dehydrogenation of trace organic compounds adsorbed on potassium niobate, rather than to the photodecomposition of water. The quantum efficiency of the photocatalytic dehydrogenation increased by an order of magnitude when hydrogen-containing organic compounds were added to the reaction mixture. 相似文献