146669-23-0Relevant articles and documents
Copper(II)-Catalyzed Reactions of α-Keto Thioesters with Azides via C-C and C-S Bond Cleavages: Synthesis of N-Acylureas and Amides
Maity, Rajib,Naskar, Sandip,Das, Indrajit
, p. 2114 - 2124 (2018/02/23)
Cu(II)-catalyzed reaction of α-keto thioesters with trimethylsilyl azide (TMSN3) proceeds with the transformation of the thioester group into urea through C-C and C-S bond cleavages, constituting a practical and straightforward synthesis of N-acylureas. When diphenyl phosphoryl azide (DPPA) is used instead as the azide source in an aqueous environment, primary amides are formed via substitution of the thioester group. The reactions are proposed to proceed through Curtius rearrangement of the initially formed α-keto acyl azide to generate an acyl isocyanate intermediate, which reacts further with an additional amount of azide or water and rearranges to afford the corresponding products. To demonstrate the potentiality of the method, one-step syntheses of pivaloylurea and isovaleroylurea, displaying anticonvulsant activities, have been carried out.
Heck-Matsuda reactions catalyzed by a hydroxyalkyl-functionalized NHC and palladium acetate
Penafiel, Itziar,Pastor, Isidro M.,Yus, Miguel
supporting information; experimental part, p. 3151 - 3156 (2012/07/03)
The functionalized NHC obtained from salt 2 is a good ligand for palladium in the Heck-Matsuda reaction of arenediazonium salts and different alkenes. The reaction is performed with low catalyst loading (0.5-1 mol-% of Pd) and in the absence of a base for acrylates. The protocol is also useful for the preparation of cinnamide derivatives. Compound U-77863 has been prepared successfully in good isolated yield. Cyclohexene was found to be an appropriate substrate for the reaction, giving the corresponding 1-arylcyclohexene as a single regioisomer under the studied reaction conditions. The optimal parameters of the reaction were studied by employing a design of experiments approach. Thus, the use of a small set of reactions allows the trends of the different factors to be studied. This study revealed that the best catalytic system is formed by combination of Pd(OAc)2 and salt 2 in a 1:2 ratio. This catalytic system produces better results without the use of a base. Copyright
The Heck reaction of β-arylacrylamides: An approach to 4-aryl-2-quinolones
Bernini, Roberta,Cacchi, Sandro,De Salve, Ilse,Fabrizi, Giancarlo
, p. 2947 - 2952 (2008/02/12)
The Heck reaction of β-arylacrylamides with aryl iodides afforded the corresponding vinylic substitution products usually in high yields. The nature of β-substituents, aryl iodides and substituents at the nitrogen atom influences the stereochemical outcome. N,N-Dimethyl-β-arylacrylamides gave vinylic substitution products with higher stereoselectivity than the corresponding N-unsubstituted β-arylacrylamides. β-Arylacrylamides containing ortho-substituents led to the formation of only one stereoisomer. The procedure was used to prepare 4-aryl-2-quinolones from β-(obromophenyl) acrylamide through a sequential Heck reaction and copper-catalyzed cyclization process. Georg Thieme Verlag Stuttgart.
