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11.
Roberto Ballini Giovanna BosicaDamiana Livi Alessandro PalmieriRaimondo Maggi Giovanni Sartori 《Tetrahedron letters》2003,44(11):2271-2273
The N,N-diethylpropylamine supported on amorphous silica (KG-60-NEt2) catalyses the formation of carboncarbon bonds by nitroalkanes through both the nitroaldol (Henry) and Michael reactions. The catalyst shows general utility with a variety of electrophilic acceptors. Moreover, the catalyst can be reused for two further cycles without loss of the activity. 相似文献
12.
A new method was developed for the synthesis of -alkyl- and ,-dialkyl--phenyltryptamines based on alkylation of nitroalkanes with -phenyl-nor-gramine. 相似文献
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Melissa L. P. Price Dennis Ostrovsky William L. Jorgensen 《Journal of computational chemistry》2001,22(13):1340-1352
Nonbonded and torsional parameters for carboxylate esters, nitriles, and nitro compounds have been developed for the OPLS‐AA force field. In addition, torsional parameters for alkanes have been updated. These parameters were fit to reproduce ab initio gas‐phase structures and conformational energetics, experimental condensed‐phase structural and thermodynamic properties, and experimental free energies of hydration. The computed densities, heats of vaporization, and heat capacities for fifteen liquids are in excellent agreement with experimental values. The new parameters permit accurate molecular modeling of compounds containing a wider variety of functional groups, which are common in organic molecules and drugs. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1340–1352, 2001 相似文献
14.
S Li K Huang B Cao J Zhang W Wu X Zhang 《Angewandte Chemie (International ed. in English)》2012,51(34):8573-8576
Building the building blocks: A highly enantioselective hydrogenation of β-aryl-β-alkyl disubstituted nitroalkenes 1 has been developed. This method results in enantiomerically pure nitroalkanes 2, which are versatile precursors for chemical synthesis. 相似文献
15.
Abstract Solutions of 1° and 2° nitroalkanes were thermolyzed in the presence of amines at hydrostatic pressures up to 1.5 GPa, and their rates of decomposition were measured. The probable mechanism of base catalyzed decomposition involves a bimolecular reaction of the aci-nitroalkane with the nitronate ion to yield a carbonyl compound, its corresponding oxime, and nitrite ion as the early rate determining steps. In the case of nitroethane, the products react further to give 3,4,5-trimethylisoxazole as a major product above 0.4 GPa. The effects of pressure on the rates of decomposition of nonacidic nitroalkanes, 2,2-dinitropropane and 2-methyl-2-nitropropane, were measured and used to infer the rate-controlling steps. 2,2-Dini-tropropane appears to undergo rearrangement to a nitrite, followed by homolysis to give acetone, NO and NO2. 2-Methyl-2-nitropropane gives mostly isobutylene and HONO, probably via a 5-membered cyclic transition state. 相似文献
16.
Dr. Margherita Pirola Dr. Chiara Faverio Dr. Manuel Orlandi Prof. Dr. Maurizio Benaglia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(40):10247-10250
A metal-free, mild and chemodivergent transformation involving nitroalkanes has been developed. Under optimized reaction conditions, in the presence of trichlorosilane and a tertiary amine, aliphatic nitroalkanes were selectively converted into amines or nitriles. Furthermore, when chiral β-substituted nitro compounds were reacted, the stereochemical integrity of the stereocenter was maintained and α-functionalized nitriles were obtained with no loss of enantiomeric excess. The methodology was successfully applied to the synthesis of chiral β-cyano esters, α-aryl alkylnitriles, and TBS-protected cyanohydrins, including direct precursors of four active pharmaceutical ingredients (ibuprofen, tembamide, aegeline and denopamine). 相似文献
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Slepukhin P. A. Rusinov G. L. Charushin V. N. Filyakova V. I. Karpenko N. S. Krivolapov D. B. Litvinov I. A. 《Russian Chemical Bulletin》2004,53(6):1272-1278
Products of diaddition of O- and C-nucleophiles to the 2,3-dicyano-1-ethylpyrazinium cation were isolated for the first time. The tandem AN—AN reactions of 2,3-dicyano-1-ethylpyrazinium tetrafluoroborate with 1,3-diketone enolates or keto esters afforded tetrahydrofuro[2,3-b]pyrazine derivatives, whereas cyclization with ethylene glycol gave tetrahydro-1,4-dioxino[2,3-b]pyrazine. Crystallographic data on the three-dimensional structures of these compounds were reported. 相似文献
19.
《Mendeleev Communications》2023,33(4):461-462
A concise safe approach for selective nitration and nitroxylation of tert-alkanes, in particular adamantane, and tert-alkyl bromides utilizing NO2 in supercritical CO2 medium has been established. Major reaction products were tert-alkyl nitro compounds and tert-alkyl nitrates depending on the reaction conditions. 相似文献
20.
Alexander V. Aksenov Nicolai A. Aksenov Elena V. Aleksandrova Dmitrii A. Aksenov Igor Yu. Grishin Elena A. Sorokina Allison Wenger Michael Rubin 《Molecules (Basel, Switzerland)》2021,26(20)
The recently discovered [4+1]-spirocyclization of nitroalkenes to indoles provided a convenient new approach to 2-(1H-indol-2-yl)acetonitriles. However, this reaction was complicated by the formation of inert 3-(2-nitroethyl)-1H-indole byproducts. Herein, we offer a workaround this problem that allows for effective transformation of the unwanted byproducts into acetonitrile target molecules. 相似文献