13673-03-5Relevant articles and documents
2-methyl-4-phenyl-1-pyrroline preparation method
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Paragraph 0031; 0032, (2017/09/05)
The invention discloses a 2-methyl-4-phenyl-1-pyrroline preparation method which includes the steps: S1, preparing phenyl nitro ethylene from benzaldehyde and nitromethane under catalysis of alkali metal hydroxide; S2, performing addition reaction on the phenyl nitro ethylene and acetone under catalysis of L-proline; S3, performing reduction and ring-closure on an addition product to obtain a target product. According to the preparation method, synthetic raw materials are easily obtained and low in price, and operation conditions are mild. Routes are simple and convenient in synthesis, silica-gel column chromatography is omitted after each step of reaction, and the preparation method is suitable for scientific research of laboratory mini-preparation and industrial production and amplification. Technical improvement of related drugs can be promoted, and various rich routes are provided for synthesis of the drugs.
Intramolecular hydroamination of unbiased and functionalized primary aminoalkenes catalyzed by a rhodium aminophosphine complex
Julian, Lisa D.,Hartwig, John F.
supporting information; experimental part, p. 13813 - 13822 (2010/11/17)
We report a rhodium catalyst that exhibits high reactivity for the hydroamination of primary aminoalkenes that are unbiased toward cyclization and that possess functional groups incompatible with more electrophilic hydroamination catalysts. The rhodium catalyst contains an unusual diaminophosphine ligand (L1) that binds to rhodium in a K3-P,O,P mode. The reactions catalyzed by this complex typically proceed at mild temperatures (room temperature to 70 °C) and occur with primary aminoalkenes lacking substituents on the alkyl chain that bias the system toward cyclization, with primary aminoalkenes containing chloride, ester, ether, enolizable ketone, nitrile, and unprotected alcohol functionality, and with primary aminoalkenes containing internal olefins. Mechanistic data imply that these reactions occur with a turnover-limiting step that is different from that of reactions catalyzed by late-transition-metal complexes of Pd, Pt, and Ir. This change in the turnover-limiting step and resulting high activity of the catalyst stem from favorable relative rates for protonolysis of the M-C bond to release the hydroamination product versus reversion of the aminoalkyl intermediate to regenerate the acyclic precursor. Probes of the origin of the reactivity of the rhodium complex of L1 imply that the aminophosphine groups lead to these favorable rates by effects beyond steric demands and simple electron donation to the metal center.
Synthetic Versatility of N(Silylmethyl)imines: Water-Induced Generation of N-Protonated Azomethine Ylides of Nonstabilized Type and Fluoride-Induced Generation of 2-Azallyl Anions
Tsuge, Otohiko,Kanemasa, Shuji,Hatada, Akira,Matsuda, Koyo
, p. 2537 - 2546 (2007/10/02)
N-(Silylmethyl)imines generate N-protonated azomethine ylides of nonstabilized type when treated with water in HMPA, which undergo stereospecific and regioselective cycloadditions with electron-poor olefins affording N-unsubstituted pyrrolidines.On the other hand, fluoride-induced desilylation of the imines leads to 2-azallyl anions which are found to be synthetic equivalents of aminomethyl anion in the Michael additions with electron-poor olefins and nucleophilic additions with carbonyl compounds.
