43008-56-6Relevant academic research and scientific papers
N-Heterocyclic Carbene/Cobalt Cooperative Catalysis for the Chemo- and Regioselective C?N Bond Formation between Aldehyde and Amines/Amides
Siddiqui, Asher M.,Khalid, Anam,Khan, Arif,Azad, Chandra S.,Samim, Mohd.,Khan, Imran A.
, p. 4281 - 4287 (2020/07/24)
A novel methodology for the construction of various secondary (4 examples), tertiary amides (31 examples), and imides (16 examples) by a Cobalt(II) catalyzed oxidative amide coupling in aqueous media. The Co(III)-TMC was reacted with N-Heteroatom Carbene to form active catalyst Co(II)NHC-TMC in situ which involves in the coordination with Breslow's intermediate and SET for the activation of aldehyde and amides. The mechanism for activation of amide and amine differs on the basis of SET based nucleophilic addition and ligand exchange respectively. The regeneration of the catalyst was achieved using Fe(III)(EDTA)-H2O2 as oxidant. The use of Co(II)TMC-O2 was also found equally efficient in the process. The method is found regioselective for N?H activation in the presence of equally susceptible ortho-C?H bond activation. And amines were found more susceptible then the corresponding amide for the reaction.
The versatile conversion of acyclic amides to α-alkylated amines
Suh, Young-Ger,Shin, Dong-Yun,Jung, Jae-Kyung,Kim, Seok-Ho
, p. 1064 - 1065 (2007/10/03)
A general and efficient method for the versatile functionalization of acyclic amide via N,O-acetal TMS ether, an excellent precursor for the N-acyliminium ion, has been developed.
Selective Cathodic Cleavage of Unsymmetrical Imidodicarbonates, Acylcarbamates and Diacylamides
Maia, Hernani L. S.,Monteiro, Luis S.,Degerbeck, Fredrik,Grehn, Leif,Ragnarsson, Ulf
, p. 495 - 500 (2007/10/02)
A study of the selective cathodic cleavage of one of the alkoxycarbonyl or acyl groups from various imidodicarbonates, acylamides, and diacylamides is reported.The compounds investigated include all 15 possible combinations of the following groups in unsymmetrical N,N-diprotected derivatives of benzylamine: p-nitrobenzyloxycarbonyl, trichloroethyloxycarbonyl, toluene-p-sulfonyl, benzoyl, benzyloxycarbonyl, and tert-butyloxycarbonyl which can all be electrochemically cleavaged, except the last one.Initially the compounds were examined by cyclic voltammetry in order to measure the potentials associated with the cleavage of each group and afterwards they were electrolysed at constant potential in the presence of a proton donor.The following ranges in negative potential were recorded: 1.03-1.13 V , 1.8-2.14 V (Troc), 1.75-2.41 V (Tos), 1.88-2.52 V (Bz), and 2.83-2.9 V (Z), thus occasionally revealing a drastic effect of the auxiliary group.In the eletrolytic experiments competitive attack by base occasionally led to mixtures of monoacylamides.However, all compounds apart from some of the trichloroethyloxycarbonyl derivatives could be selectively cleaved in 89-100percent yields when an appropriate proton donor was used.Tentative explanations are given for the behaviour of the compounds studied and some conclusions are drawn.
Acidity of Benzoylcarbamates in Dimethyl Sulfoxide. Confirmation of Mixed N/O Alkylation in the Mitsunobu Reaction
Koppel, Ilmar,Koppel, Juta,Koppel, Ivar,Leito, Ivo,Pihl, Viljar,et al.
, p. 655 - 658 (2007/10/02)
Seventeen benzoyl-, 4-methoxybenzoyl-, and 4-nitrobenzoyl-carbamates have been synthesized via their corresponding isocyanates and their acidities determined in dimethyl sulfoxide solution.Their pKa values span an interval of nearly 5 pK units
