14040-77-8Relevant articles and documents
Novel syntheses of oxamides, oxamates and oxalates from diisopropenyl oxalate
Neveux, Muriel,Bruneau, Christian,Lecolier, Serge,Dixneuf, Pierre H.
, p. 2629 - 2640 (1993)
Diisopropenyl oxalate, obtained by catalytic addition of oxalic acid to propyne, is a useful reagent for the access to a variety of α-dicarbonyl compounds such as oxamides, oxamates and oxalates, under very mild conditions.
Visible-Light-Induced Palladium-Catalyzed Dehydrogenative Carbonylation of Amines to Oxalamides
Meyer, Tim,Rabeah, Jabor,Brückner, Angelika,Wu, Xiao-Feng
supporting information, p. 5642 - 5647 (2021/03/09)
The palladium-catalyzed oxidative carbonylation of amines toward the synthesis of oxalamides has been established around 30 years ago and it usually needs the presence of (over)stoichiometric amounts of oxidant. In this work, the first transformation of this type in which the oxidant was replaced by visible light is described. The new approach uses a simple robust Pd complex, which can even be partially recycled. A mechanistic reason is provided and supported by control experiments and EPR studies, showing that PdI was formed and Pd0 was the active species. Both nitrogen- and the intermediate acyl radical can be detected. Moreover, the formation of hydrogen was confirmed by gas GC.
Selective oxidative carbonylation of amines to oxamides and ureas catalyzed by palladium complexes
Hiwatari, Kozo,Kayaki, Yoshihito,Okita, Koshi,Ukai, Tomohiro,Shimizu, Isao,Yamamoto, Akio
, p. 2237 - 2250 (2007/10/03)
A new process for converting secondary amines into N,N,N′,N′- tetraalkyloxamides under CO pressure, catalyzed by homogeneous palladium complexes in the presence of 1,4-dichloro-2-butene (DCB) as an oxidant, has been developed. The mechanism of the oxidative double-carbonylation process, consisting of the oxidation of Pd(0) to Pd(11) with DCB through a β-chloride elimination of the η3-(chloromethyl) allylpalladiuni(11) intermediate, the formation of mono- and bis(carbamoyl)palladium species, and a reductive elimination of the two carbamoyl ligands, is proposed based on studies of the behavior of carbamoylpalladium complexes. When primary amines are employed with DCB as the oxidant, N,N′-dialkyloxamide is catalytically produced, whereas urea is exclusively produced when iodine is used as the oxidant. The reaction of an N-monopropylcarbamoylpalladium complex with propylamine under CO gave N,N′-dipropylurea, whereas a treatment with diethylamine yielded unsymmetrical N,N-diethyl-N′-propylurea, implying the intermediate formation of propyl isocyanate that is converted into the urea upon a reaction with the added amine. A kinetic study on the reaction of chloro-N- propylcarbamoylpalladium with triethylamine suggested a process proceeding through a base-promoted dcprolonalion of the N-monoalkylcarbamoyl ligand to form propyl isocyanate.