56146-87-3Relevant articles and documents
A Practical and General Amidation Method from Isocyanates Enabled by Flow Technology
Williams, Jason D.,Kerr, William J.,Leach, Stuart G.,Lindsay, David M.
supporting information, p. 12126 - 12130 (2018/09/11)
The addition of carbon nucleophiles to isocyanates represents a conceptually flexible and efficient approach to the preparation of amides. This general synthetic strategy has, however, been relatively underutilized owing to narrow substrate tolerance and the requirement for less favourable reaction conditions. Herein, we disclose a high-yielding, mass-efficient, and scalable method with appreciable functional group tolerance for the formation of amides by reaction of Grignard reagents with isocyanates. Through the application of flow chemistry and the use of substoichiometric amounts of CuBr2, this process has been developed to encompass a broad range of substrates, including reactants found to be incompatible with previously published procedures.
Uncovering the importance of proton donors in TmI2-promoted electron transfer: Facile C-N bond cleavage in unactivated amides
Szostak, Michal,Spain, Malcolm,Procter, David J.
supporting information, p. 7237 - 7241 (2013/07/26)
Nonclassical lanthanide(II) iodides are modern reagents for the development of challenging electron-transfer processes. It was demonstrated that alcohols are critical for the formation of a thermodynamically more powerful reductant from TmI2 (thulium diiodide), the first nonclassical lanthanide(II) iodide in the series (TmI2, DyI2, NdI2). The TmI2(ROH)n reagent promotes an unprecedented cleavage of the σ C-N bond in amides. Copyright
Pseudomonas stutzeri lipase: A useful biocatalyst for aminolysis reactions
Van Pelt,Teeuwen,Janssen,Sheldon,Dunn,Howard,Kumar,Martinez,Wong
experimental part, p. 1791 - 1798 (2011/10/09)
The use of Pseudomonas stutzeri lipase (PSL) as a biocatalyst for aminolysis reactions with bulky substrates has been investigated. PSL compared favorably to Novozym 435 (immobilized Candida antarctica lipase B, NOV435) in the aminolysis of various bulky methyl esters and amines. While NOV435 demonstrated a higher rate of aminolysis with methyl 2-phenylpropionic acid as the acyl donor, PSL outperformed NOV435 with secondary amines as the nucleophile. Methanol inhibition and a low affinity for bulky acyl donors were found to be the two main reasons for relatively low rates in the PSL-catalyzed aminolysis reactions. It was demonstrated that the use of molsieve 4A had a significant effect on the aminolysis rate and amide yield, since it enabled the effective removal of the inhibiting methanol from the reaction mixture.
Hydrogenation of BF2 complexes with 1,3-dicarbonyl ligands
?tefane, Bogdan,Polanc, Slovenko
experimental part, p. 2339 - 2343 (2009/07/18)
The catalytic hydrogenation (H2, Pd/C) of a set of BF2 complexes with a 1,3-dicarbonyl structural unit leading to monocarbonyl compounds has been studied. The transformation presented is general for the aryl-substituted derivatives and occurs under mild conditions (H2, 1 bar, 25 °C) in methanol or THF.
Practical access to amines by platinum-catalyzed reduction of carboxamides with hydrosilanes: Synergy of dual Si-H groups leads to high efficiency and selectivity
Hanada, Shiori,Tsutsumi, Emi,Motoyama, Yukihiro,Nagashima, Hideo
supporting information; experimental part, p. 15032 - 15040 (2010/01/29)
The synergetic effect of two Si-H groups leads to efficient reduction of carboxamides to amines by platinum catalysts under mild conditions. The rate of the reaction is dependent on the distance of two Si-H groups; 1,1,3,3-tetramethyldisiloxane (TMDS) and 1,2-bis(dimethylsilyl)benzene are found to be an effective reducing reagent. The reduction of amides having other reducible functional groups such as NO2, CO2R, CN, CdC, Cl, and Br moieties proceeds with these groups remaining intact, providing a reliable method for the access to functionalized amine derivatives. The platinum-catalyzed reduction of amides with polymethylhydrosiloxane (PMHS) also proceeds under mild conditions. The reaction is accompanied by automatic removal of both platinum and silicon wastes as insoluble silicone resin, and the product is obtained by simple extraction. A mechanism involving double oxidative addition of TMDS to a platinum center is discussed.
The ruthenium-catalyzed reduction and reductive N-alkylation of secondary amides with hydrosilanes: Practical synthesis of secondary and tertiary amines by judicious choice of hydrosilanes
Hanada, Shiori,Ishida, Toshiki,Motoyama, Yukihiro,Nagashima, Hideo
, p. 7551 - 7559 (2008/02/12)
(Chemical Equation Presented) A triruthenium cluster, (μ3, η2,η3,η5-acenaphthylene)Ru 3(CO)7 (1) catalyzes the reaction of secondary amides with hydrosilanes, yielding a mixture of secondary amines, tertiary amines, and silyl enamines. Production of secondary amines with complete selectivity is achieved by the use of higher concentration of the catalyst (3 mol %) and the use of bifunctional hydrosilanes such as 1,1,3,3-tetramethyldisiloxane. Acidic workup of the reaction mixture affords the corresponding ammonium salts, which can be treated with a base, providing a facile method for isolation of secondary amines with high purity. In contrast, tertiary amines are formed with high selectivity by using lower concentration of the catalyst (1 mol %) and polymeric hydrosiloxanes (PMHS) as reducing agent. Reduction with PMHS encapsulates the ruthenium catalyst and organic byproducts to the insoluble silicone resin. The two reaction manifolds are applicable to various secondary amides and are practical in that the procedures provide the desired secondary or tertiary amine as a single product. The product contaminated with only minimal amounts of ruthenium and silicon residues. On the basis of the products and observed side products as well as NMR studies a mechanistic scenario for the reaction is also described.
Uncatalyzed conversion of linear α-nitro ketones into amides by reaction with primary amines under solventless conditions
Ballini, Roberto,Bosica, Giovanna,Fiorini, Dennis
, p. 1143 - 1145 (2007/10/03)
The reaction of linear α-nitro ketones with primary amines allows the formation of amides through the cleavage of the carbon-carbon bond between the carbonyl group and the carbon-nitro group moiety, promoted by the nucleophilic effect of the amine. The re
Rhodium(I)-catalyzed 1,2- and 1,4-addition of aryltriethoxysilanes to carbonyl compounds under aqueous basic conditions
Murata, Miki,Shimazaki, Ryuta,Ishikura, Masanori,Watanabe, Shinji,Masuda, Yuzuru
, p. 717 - 719 (2007/10/03)
Aryltriethoxysilanes add to aldehydes and α,β-unsaturated carbonyl compounds in high yield in the presence of a rhodium(I) catalyst and aqueous sodium hydroxide.
The Favorskii Rearrangement of α-Chloro Ketimines
Kimpe, Norbert De,Sulmon, Paul,Moeens, Luc,Schamp, Niceas,Declercq, Jean-Paul,Meerssche, Maurice Van
, p. 3839 - 3848 (2007/10/02)
The Favorskii rearrangement of α-chloro ketimines has been studied.It was shown that the base-induced rearrangement of α-chloro ketimines afforded imidates or amides via a mechanism involving 1,3-dehydrochlorination and ring-opening of the resulting cyclopropylideneamines.The ring-opening occurred in such a way as to produce the most stable carbanion.The entire mechanism paralleled the well-known cyclopropanone mechanism of the Favorskii rearrangement of the corresponding oxygen analogues, i.e., α-halo ketones.Evidence has been presented that the semibenzilic-type mechanism is not operative in the cases studied.Depending upon the reaction conditions and the substrate, the Favorskii rearrangement was accompanied by various side reactions including nucleophilic substitution, 1,2-dehydrochlorination, rearrangement via intermediate α-alkoxyaziridines, and self-condensation.
