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1.
Chem Commun (Camb) ; 59(51): 7986-7989, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37284787

RESUMEN

From a single alkene to two different alkenes! An iron-catalyzed four-component reaction involving an aldehyde, two different alkenes and TMSN3 is developed to assemble these four reactants in an orderly fashion based on the inherent nucleophilic/electrophilic reaction activity of the radicals and alkenes via a double radical addition, providing various multifunctional compounds containing an azido group and two carbonyl groups.


Asunto(s)
Alquenos , Hierro , Catálisis , Aldehídos
2.
Org Lett ; 22(17): 6776-6779, 2020 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-32820933

RESUMEN

From a single alkene to two different alkenes! A convenient Fe-catalyzed A-D-A-T-type radical-dual-difunctionalization and cross-coupling of two different alkenes to provide chain elongated and trifluoromethylated aromatic alkenes has been developed.

3.
Molecules ; 25(3)2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31972970

RESUMEN

For the convenient introduction of simple linear/branched alkyl groups into biologically important azaspirocyclohexadienones, a practical Fe-catalyzed decarbonylative cascade spiro-cyclization of N-aryl cinnamamides with aliphatic aldehydes to provide alkylated 1-azaspiro-cyclohexadienones was developed. Aliphatic aldehydes were oxidative decarbonylated into primary, secondary and tertiary alkyl radicals conveniently and allows for the subsequent cascade construction of dual C(sp3)-C(sp3) and C=O bonds via radical addition, spirocyclization and oxidation sequence.


Asunto(s)
Alquilantes/química , Compuestos Aza/química , Cinamatos/química , Ciclohexenos/química , Hierro/química , Compuestos de Espiro/química , Aldehídos/química , Alquilación , Catálisis , Ciclización
4.
Chem Commun (Camb) ; 55(80): 12080-12083, 2019 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-31538178

RESUMEN

From difunctionalization of a single alkene to radical-dual-difunctionalization of two different alkenes! Abundant aliphatic aldehydes were readily decarbonylated into alkyl radicals for the cascade construction of C(sp3)-C(sp3), C(sp3)-C(sp3) and C(sp3)-O bonds via double radical addition and radical-radical coupling, following the intrinsic nucleophilic/electrophilic reactivity of both the radicals and alkenes.

5.
Org Lett ; 21(15): 6117-6121, 2019 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-31322353

RESUMEN

A convenient Fe-catalyzed four-component radical dual difunctionalization and ordered assembly of two alkenes with aromatic/aliphatic aldehydes and TBHP to provide chain elongated ß,δ-functionalized ketones via a one-pot procedure has been developed. Aldehydes were homolytically cleavaged to produce acyl radicals and subsequently allowed for the successive construction of C(sp2)-C(sp3), C(sp3)-C(sp3), and C(sp3)-O bonds via dual radical insertions and radical-radical coupling, following the intrinsic nucleo/electrophilic reactivity of both the radicals and alkenes.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(3): 777-81, 2014 Mar.
Artículo en Chino | MEDLINE | ID: mdl-25208411

RESUMEN

This paper made use of three-dimensional fluorescence and ultraviolet-absorption spectrum to analyze the spectral characteristics of etroleum ether extract from Guizhou flue-cured tobacco and the overall characteristic spectral information of tobacco chemical substances were obtained. The three dimensional fluorescence and ultraviolet-visible absorption spectrum of each petroleum ether extract of flue-cured tobacco from different areas are generally similar, but their intensity is different. There have three characteristic peaks in three dimensional fluorescence spectra: I: Ex/Em = 297/326 nm, II: Ex/Em = 250/330 nm, III: Ex/Em = 225/336 nm respectively and meanwhile the order of these peaks intensity is I > III > II. The ultraviolet-visible absorption spectrum in 300-300 nm range presents four characteristic absorption peaks, whose maximum absorption wavelength are 329, 419, 445 and 419 nm respectively. Meanwhile, in accord with the relative intensity of characteristic peaks, it is known that there exist differences in the relative contents of the total chemical substances obtained from different flavor styles of the flue-cured tobacco. The clustering analysis results of three-dimensional fluorescence intensity score (D) and intensity ratio (R) show that in a certain range of distance coefficient, the flue-cured tobacco from different regions in Guizhou can be clearly divided into two classes "mildly sweet "and "alcohol sweet ". The classification can be well achieved in the smaller distance coefficient according to the ratio cluster of fluorescence intensity instead of the score cluster of fluorescence intensity. The method of three-dimensional fluorescence was better than that of ultraviolet-visible spectrometry in the matter of the clustering characteristic.


Asunto(s)
Nicotiana/clasificación , Odorantes/análisis , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
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