- Synthetic method of malonate compound
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The invention discloses a synthetic method of a malonate compound. The method comprises the following steps: taking 3-halogenated propargyl compound as shown in a formula 1, alcohol as shown in a formula 2 and water as raw materials; placing the raw materials in an air atmosphere and at the room temperature to react under the conditions of a palladium catalyst and alkali to prepare the malonate compound as shown in a formula 3.
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Paragraph 0045-0047
(2018/05/16)
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- Palladium-Catalyzed C-H Monoalkoxylation of α,β-Unsaturated Carbonyl Compounds
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An efficient method for the direct introduction of alkoxy groups into the β-position of alkene moieties of various α,β-unsaturated carbonyl compounds through the palladium-catalyzed C(sp2)-H monoalkoxylation using alcohols in the presence of sodium nitrite was developed; the corresponding enol ethers were selectively synthesized with minimal generation of acetals.
- Monguchi, Yasunari,Kunishima, Kouki,Hattori, Tomohiro,Takahashi, Tohru,Shishido, Yuko,Sawama, Yoshinari,Sajiki, Hironao
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p. 3994 - 3997
(2016/07/06)
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- Synthesis and decarboxylation of Δ2-cephem-4,4-dicarboxylic acids
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Penicillin V was converted in 14 steps into Δ2-cephems having hydrogen at C-3, hydrogen or methyl at C-2, and two methoxycarbonyl, two benzyloxycarbonyl, or one methoxycarbonyl and one benzyloxycarbonyl substituent at C-4. Deprotection of these Δ2-cephem-4,4-dicarboxylic acid esters by alkaline hydrolysis (in the case of methyl esters) or hydrogenolysis (in the case of benzyl esters) led in all cases to rapid decarboxylation of the Δ2-cephem-4,4-dicarboxylic acid or Δ2-cephem-4,4-dicarboxylic acid monoester. With hydrogen at C-2, hydrolysis of the dimethyl ester with 1 equiv of base produced a Δ2-cephem. With 2 equiv of base, and with all compounds having methyl at C-2, hydrolysis or hydrogenolysis afforded 4α-substituted-Δ2-cephems. In contrast, simpler benzyl or methyl acetamidomalonates could be deprotected without difficulty to afford stable malonic acids. Reasons for the differences in ease of decarboxylation were examined using semiempirical (AM1) and ab initio (3-21G) molecular orbital calculations. The decarboxylation barriers of unionized cephem or acetamido malonic acids were found to be high (35-40 kcal mol-1). Although the monoanion of acetamidomalonic acid retained a high barrier, the epimeric monoanions of a Δ2-cephem malonic acid decarboxylated with barriers of only 2 kcal mol-1.
- Wolfe,Ro,Kim,Shi
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p. 1238 - 1258
(2007/10/03)
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- Heterocyclic amines having central nervous system activity
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Tricyclic nitrogen containing compounds, having central nervous system activity of the following structural formula: STR1 and pharmaceutically acceptable salts thereof wherein R1, R2, and R3 are independently hydrogen, C1-6 alkyl, alkenyl, or alkynyl, C3-10 cycloalkyl, or R1 and R2 are joined to form a C3-7 cyclic amine which can contain additional heteroatoms; X is hydrogen, C1-6 alkyl halogen, hydroxy, alkoxy, cyano, carboxamide, carboxyl, or carboalkoxyl; A is SO2, N, CH, CH2, CHCH3, C=O, C=S, C-SCH3, C=NH, C-NH2, C-NHCH3, C--NHCOOCH3, or C--NHCN. B is CH2, CH, C=O, N, NH or N--CH3 ; n is 0 or 1; and D is CH, CH2, C=O, O, N, NH or N--CH3. These new compounds are suitable for treating schizophrenia, Parkinson's disease, anxiety, depression or as compounds for lowering blood pressure in animal or human hosts.
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- A MILD, RAPID AND CONVENIENT ESTERIFICATION OF HALF ESTERS OF MALONIC ACID
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A new method for the esterification of half esters of malonic acid with chloroformates is described.The reaction proceeds via the mixed anhydride followed by spontaneous decarboxylation.
- Gutman, Arie L.,Boltanski, Aviv
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p. 1573 - 1576
(2007/10/02)
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- FLASH PYROLYSIS: A ROUTE TO "α-KETENIC ESTERS".
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3-Oxo 2-propenoic acid methyl ester has been prepared by flash vacuum pyrolysis and characterized by mass spectrometry and chemical trapping.Its four-membered cyclic dimers have been isolated.
- Jullien, J.,Pechine, J. M.,Perez, F.
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p. 5525 - 5526
(2007/10/02)
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