614-20-0Relevant articles and documents
Fixation of carbon dioxide by oxalic amidinato magnesium complexes: Structures and reactions of trimetallic magnesium carbamato and related complexes
Ruben, Mario,Walther, Dirk,Knake, René,G?rls, Helmar,Beckert, Rainer
, p. 1055 - 1064 (2000)
The reaction of oxalic amidines R1-N=C(NHR2)-C(NHR2)=N-R1 with CH3MgX followed by uptake of CO2 results in the formation of the trimeric carbamato complexes [R1-N=C(NR2-COO)-C(NR2-COO)-C(NR2COO)=N- R1]3Mg3(THF)6 (2a: R1 = R2 = Ph; 2b: R1 = R2 = p-tolyl) as the thermodynamically stable final products of the reaction. Their X-ray crystal structures show that the three metal centres are in a linear arrangement. The central magnesium ion is octahedrally surrounded by six O-donor atoms of the μ2-carbamato bridges, while both peripheral magnesium ions are facially coordinated by three O-donor atoms of the carbamato groups and three THF molecules. This coordination sphere can be considered as a structural model for the active centre in the ribulose-1,5-bisphosphate carboxylase/oxygenase enzyme. Compound 2a reacts with ZnCl2 or CoBr2, with CO2 elimination, to form dimeric complexes of the type [X2M(oxalamidinato)MX2][Mg(DMF)6] (M = Zn, Co; X = Cl, Br). X-ray crystal structure analyses show that the d-metals are tetrahedrally coordinated. The magnesium-bromide-containing intermediates in the formation of 2a and 2b are able to transfer CO2 to acetophenone, thus simulating the CO2 activation step in enzymatic biotin-dependent carboxylation reactions.
Synthetic method of lobeline hydrochloride
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Paragraph 0006; 0027; 0030; 0032; 0034, (2021/06/09)
The invention relates to the technical field of medicine synthesis, and particularly discloses a method for synthesizing lobeline hydrochloride. The method comprises the following steps: performing acylation reaction on ethyl acetoacetate and benzoyl chloride serving as raw materials in the presence of NaOH, NH4Cl and the like, performing hydrolysis reaction on the obtained ethyl benzoylacetate in water in the presence of potassium hydroxide to obtain benzoylacetic acid, carrying out a condensation reaction with glutaraldehyde and methylamine hydrochloride in a citric acid buffer solution, carrying out a reduction reaction on lobeline diketone hydrochloride obtained by the condensation reaction in a mixed solution composed of potassium borohydride, activated carbon, sodium hydroxide and methanol, quenching the reducing agent in the obtained reaction liquid by sulfuric acid, sequentially filtering, extracting, concentrating, cooling and crystallizing to obtain lobeline racemate, then adding L-DBTA, and sequentially performing resolution, dissociation and hydrochlorination to obtain lobeline hydrochloride. The synthesis method has the characteristics of few synthesis steps, simple synthesis conditions, convenience in operation and the like, and the used raw materials have the characteristics of wide source, low price and the like.
Double decarboxylative route to 3-substituted pyrrolidines: Reaction of monoalkyl malonates and related carboxylic acids with sarcosine and formaldehyde
Buev, Evgeny M.,Smorodina, Anastasia A.,Moshkin, Vladimir S.,Sosnovskikh, Vyacheslav Y.
supporting information, (2020/02/22)
Three-component reactions of monoalkyl malonates, cyanoacetic acids or 2-ketocarboxylic acids, N-methylglycine, and formaldehyde were developed to rapidly access 3-substituted pyrrolidines in 17–97% yield. These reactions represent a double decarboxylative domino-sequence promoted by pyrrolidine and involve N-methylazomethine ylide as the reactive intermediate.
CO2-Folded Single-Chain Nanoparticles as Recyclable, Improved Carboxylase Mimics
Chen, Liang,Yan, Qiang,Zeng, Rongjin
supporting information, p. 18418 - 18422 (2020/08/21)
Emulating the function of natural carboxylases to convert CO2 under atmospheric condition is a great challenge. Herein we report a class of CO2-folded single-chain nanoparticles (SCNPs) that can function as recyclable, function-intensified carboxylase mimics. Lewis pair polymers containing bulky Lewis acidic and basic groups as the precursor, can bind CO2 to drive an intramolecular folding into SCNPs, in which CO2 as the folded nodes can form gas-bridged bonds. Such bridging linkages highly activate CO2, which endows the SCNPs with extraordinary catalytic ability that can not only catalyze CO2-insertion of C(sp3)-H for imitating the natural enzyme's function, it can also act on non-natural carboxylation pathways for C(sp2 and sp)-H substrates. The nanocatalysts are of highly catalytic efficiency and recyclability, and can work at room temperature and near ambient CO2 condition, inspiring a new approach to sustainable C1 utilization.
