Unsaturated compounds containing nitrogen. Part 4. Further reactions of 1-chloro-2,3-diazabutadienes with S-nucleophiles
作者:William T. Flowers、John F. Robinson、David R. Taylor、Anthony E. Tipping
DOI:10.1039/p19810000349
日期:——
1-Chloro-1,4-diaryl-2,3-diazabutadienes (Ar1CClNNCHAr2), prepared by the reaction of thionyl chloride with aroylhydrazones (Ar1CONHNCHAr2), react with thiosemicarbazide or thiocarbohydrazide to give 2-arylidenehydrazino-5-aryl-1,3,4-thiadiazoles, and with potassium thiocyanate to give 1-thiocyanato-1,4-diaryl-2,3-diaza-butadienes which isomerize thermally to arylideneamino-5-aryl-1,3,4-thiadiazoles
Mild, Stereoselective, and Highly Efficient Synthesis of<i>N</i>-Acylhydrazones Mediated by CeCl<sub>3</sub>·7H<sub>2</sub>O in a Broad Range of Solvents
作者:José Maurício dos Santos Filho
DOI:10.1002/ejoc.201402609
日期:2014.10
This method uses a minimal catalytic amount of cerium(III), is stereoselective, and offers several unique features, such as compatibility with aryl, heterocyclic, alkenyl, and sensitive functional groups as well as the ability to prepare N-acylhydrazones from highly hindered substrates. More strikingly, cerium(III) efficiently mediated the reaction with less reactive substrates such as diaryl and alkyl
Facile preparation of allylzinc species from allylboronates and zinc amide via a boron-to-zinc exchange process and their reactions with carbonyl compounds, imines and hydrazones
作者:Yi Cui、Yasuhiro Yamashita、Shū Kobayashi
DOI:10.1039/c2cc34340a
日期:——
Facile formation of allylzinc species from allylboronate and zinc amide was discovered. The boron-to-zinc exchange process occurred smoothly to afford the corresponding allylzinc amides, which were successfully employed in catalytic allylation reactions with electrophiles. Asymmetric catalysis using a chiral zinc amide is also reported.
Thermolysis and photolysis of N-benzoylhydrazone derivatives
作者:Abd El-Aal M. Gaber、Khalid S. Khairou
DOI:10.1007/s00706-011-0532-4
日期:2011.10
N-benzoylhydrazones were subjected to thermolysis by refluxing at 200 °C. Benzil, benzoic acid, biphenyl, benzanilide together with the corresponding ketones, nitriles, substituted methanes, and imines were isolated. Similar treatment of a third hydrazone at 250 °C afforded, in addition to the previous products, toluene, bibenzyl, stilbene, and 2-phenylindole. Photolysis of the same hydrazones in acetonitrile
Catalytic Use of Zinc Amide for Transmetalation with Allylboronates: General and Efficient Catalytic Allylation of Carbonyl Compounds, Imines, and Hydrazones
The efficient catalytic allylation of ketones, imines, and hydrazones with allylboronates using a catalytic amount of zinc amide is reported. In this reaction, the boron‐to‐zinc exchange process occurred smoothly to afford the corresponding allylzinc amides, and the desired allylation reactions proceeded in high efficiency (∼0.1 mol%). A mechanistic study revealed that transmetalation was a rate‐determining