374675-64-6Relevant articles and documents
Homogeneous catalytic carbonylation of nitroaromatics. 8. Kinetic and mechanistic studies of the carbon-nitrogen bond and product forming steps from Ru(Ph2PCH2CH2PPh2)(CO) 2[C(O)OCH3]2: The turnover limiting reactions in the catalytic cycle
Gargulak, Jerry D.,Gladfelter, Wayne L.
, p. 3792 - 3800 (1994)
Mechanistic studies of the reaction of (OC-6-32)-dicarbonylbis(methoxycarbonyl)[1,2-bis(diphenylphosphino)-ethane] ruthenium(II) with p-toluidine to form N,N'-di-p-tolylurea are presented. The overall reaction was studied from 22 to 103°C and was found to be first order with respect to each reactant. Spectroscopic and kinetic studies between 22 and 52°C showed that the reaction proceeds through a species, Ru(dppe)(CO)2[C(O)OCH3] [C(O)-NH(p-tolyl)], which is in equilibrium with Ru(dppe)(CO)2[C(O)OCH3]2. The mechanism of the C-N bond forming step is proposed to involve nucleophilic attack on a coordinated Ru-CO moiety with subsequent cleavage of the C(O)-OMe bond. The methoxycarbonyl-carbamoyl complex decomposes in a unimolecular fashion to liberate CH3OH, the starting catalyst Ru(dppe)(CO)3, and p-tolyl isocyanate, which is immediately scavenged by excess amine to form N,N'-di-p-tolylurea. Studies of the analogous bis(isopropylcarbamoyl) complex provided supporting evidence for isocyanate elimination. Thermolysis of (OC-6-32)-dicarbonylbis(isopropylcarbamoyl)[1,2-bis(diphenylphosphino)-ethane] ruthenium(II) yields isopropylamine, the starting catalyst Ru(dppe)(CO)3, and isopropyl isocyanate, which reacts with isopropylamine over time to form diisopropylurea. The kinetics obtained from all of the stoichiometric reactions were combined into a suitable expression and found to lie on the same Arrhenius activation energy plot as the overall rate of the catalytic reaction.
Practical one-pot amidation of N -Alloc-, N -Boc-, and N -Cbz protected amines under mild conditions
Hong, Wan Pyo,Tran, Van Hieu,Kim, Hee-Kwon
, p. 15890 - 15895 (2021/05/19)
A facile one-pot synthesis of amides from N-Alloc-, N-Boc-, and N-Cbz-protected amines has been described. The reactions involve the use of isocyanate intermediates, which are generated in situ in the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, to react with Grignard reagents to produce the corresponding amides. Using this reaction protocol, a variety of N-Alloc-, N-Boc-, and N-Cbz-protected aliphatic amines and aryl amines were efficiently converted to amides with high yields. This method is highly effective for the synthesis of amides and offers a promising approach for facile amidation.
Synthesis and structure-activity relationship study of pyrrolidine-oxadiazoles as anthelmintics against Haemonchus contortus
Ruan, Banfeng,Zhang, Yuezhou,Tadesse, Solomon,Preston, Sarah,Taki, Aya C.,Jabbar, Abdul,Hofmann, Andreas,Jiao, Yaqing,Garcia-Bustos, Jose,Harjani, Jitendra,Le, Thuy Giang,Varghese, Swapna,Teguh, Silvia,Xie, Yiyue,Odiba, Jephthah,Hu, Min,Gasser, Robin B.,Baell, Jonathan
supporting information, (2020/02/04)
Parasitic roundworms (nematodes) are significant pathogens of humans and animals and cause substantive socioeconomic losses due to the diseases that they cause. The control of nematodes in livestock animals relies heavily on the use of anthelmintic drugs. However, their extensive use has led to a widespread problem of drug resistance in these worms. Thus, the discovery and development of novel chemical entities for the treatment of parasitic worms of humans and animals is needed. Herein, we describe our medicinal chemistry optimization efforts of a phenotypic hit against Haemonchus contortus based on a pyrrolidine-oxadiazole scaffold. This led to the identification of compounds with potent inhibitory activities (IC50 = 0.78–22.4 μM) on the motility and development of parasitic stages of H. contortus, and which were found to be highly selective in a mammalian cell counter-screen. These compounds could be used as suitable chemical tools for drug target identification or as lead compounds for further optimization.
