- Palladium-catalyzed regiodivergent hydroaminocarbonylation of alkenes to primary amides with ammonium chloride
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Palladium-catalyzed hydroaminocarbonylation of alkenes for the synthesis of primary amides has long been an elusive aim. Here, we report an efficient catalytic system which enables inexpensive NH4Cl to be utilized as a practical alternative to gaseous ammonia for the palladium-catalyzed alkene-hydroaminocarbonylation reaction. Through appropriate choice of the palladium precursors and ligands, either branched or linear primary amides can be obtained in good yields with good to excellent regioselectivities. Primary mechanistic studies were conducted and disclosed that electrophilic acylpalladium species were capable of capturing the NH2-moiety from ammonium salts to form amides in the presence of CO with NMP as a base.
- Gao, Bao,Zhang, Guoying,Zhou, Xibing,Huang, Hanmin
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p. 380 - 386
(2018/01/12)
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- Primary fatty acid amide preparation method
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The present invention provides a primary fatty acid amide preparation method. According to the present invention, under the action of a single auxiliary agent phosphine-containing transition metal catalyst or a combined auxiliary agent comprising a phosphine-free transition metal catalyst and a phosphine-containing ligand, terminally substituted olefin or cyclo-olefin, carbon monoxide and an ammonium salt are subjected to a hydrogen carboamidation reaction so as to prepare the primary fatty acid amide compound in one step; the raw material and the catalyst of the reaction are inexpensive and easy to obtain, and the synthesis process is simple, such that the synthesis cost is substantially reduced; the preparation method has characteristics of mild reaction condition and high yield, and issuitable for industrial production; and the raw material and the catalyst of the reaction are clean, non-toxic and low environment pollution.
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Paragraph 0291-0293
(2018/10/19)
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- Trimethylsilyl Cyanide - A Reagent for Umpolung, XI. On the Ambident Character of Substituted Allylic Anions.
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The dependence of the α/γ-ratio of alkylation products on several factors has been determined with 1-cyano-3-aryl-1-(trimethylsiloxy)allylic anions.Increasing amounts of γ-product are found in more polar solvents, with larger alkali ions, on addition of HMPT, with smaller alkyl groups in the electrophile, and especially with p-cyanophenyl groups.In contrast, temperature and leaving groups have minor effects.On substitution of the O-silyl group by O-methyl and O-ethoxycarbonyl, α-alkylation predominates strongly.The results are compared to known allylic anions.Furthermore, the isomerisation of compounds of type C to type B is described as well as a new addition reaction of cyanoformates to aldehydes.
- Huenig, Siegfried,Reichelt, Helmut
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p. 1772 - 1800
(2007/10/02)
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