10264-08-1Relevant articles and documents
Discovery of competing anaerobic and aerobic pathways in umpolung amide synthesis allows for site-selective amide18O-labeling
Shackleford, Jessica P.,Shen, Bo,Johnston, Jeffrey N.
, p. 44 - 46 (2012)
The mechanism of umpolung amide synthesis was probed by interrogating potential sources for the oxygen of the product amide carbonyl that emanates from the α-bromo nitroalkane substrate. Using a series of 18O-labeled substrates and reagents, evidence is gathered to advance two pathways from the putative tetrahedral intermediate. Under anaerobic conditions, a nitro-nitrite isomerization delivers the amide oxygen from nitro oxygen. The same homolytic nitro-carbon fragmentation can be diverted by capture of the carbon radical intermediate with oxygen gas (O2) to deliver the amide oxygen from O2. This understanding was used to develop a straightforward protocol for the preparation of 18O-labeled amides in peptides by simply performing the umpolung amide synthesis reaction under an atmosphere of 18O2.
Preparation of polymer-bound pyrazolone active esters for combinatorial chemistry
Byun, Jang-Woong,Lee, Dong-Hoon,Lee, Yoon-Sik
, p. 8063 - 8067 (2003)
The preparation of solid-phase active esters from a new pyrazolone linker resin is described. N-Acylation using this resin provides various amide products with a high conversion rate and good purity under mild conditions. The polymer-bound pyrazolone linkers are stable in the reaction conditions and are resistant to hydrolysis. Moreover, this resin can also be reused repeatedly without a loss of reactivity.
Amino-functionalized carbon nanotubes as nucleophilic scavengers in solution phase combinatorial synthesis
Li, Yongsheng,Zhao, Yuzeng,Zhang, Zhuo,Xu, Yaomin
, p. 1434 - 1436 (2010)
A versatile method for fast scavenging a variety of electrophiles using carbon nanotubes functionalized by amino groups (CNT-NH2) is reported. Following the scavenging event, CNT-NH2 can be easily separated from the reaction mixture by filtration, leaving the desired products in excellent yields and purities.
Synthesis of some α-ketophosphonates comprising mobile hydrogens in position α: Spectroscopic characteristics of 1H, 13C, 31P NMR and IR reactivities among amines and hydrazine derivatives
Hassen, Zied,Akacha, Azaiez Ben,Zantour, Hedi
, p. 2241 - 2253 (2003)
In the present work we describe the keto-enol equilibrium of some acylphosphonates 1 by means of 1H, 13C, 31P NMR, and IR data which show that the enol form has E configuration. The keto/enol ratio is determined on the basis of 31P NMR data. The reactivity of 1 with hydrazines derivatives and primary amines are reported. The structure of all compounds is determined by 1H, 13C, 31P NMR, and IR.
Photoinduced Carbamoylation of C(sp3)H Bonds with Isocyanates
Ishida, Naoki,Kawasaki, Tairin,Murakami, Masahiro,Tomono, Ryota,Yamazaki, Katsushi
supporting information, p. 1684 - 1684 (2021/09/16)
Alkylbenzenes coupled with isocyanates at the benzylic position upon irradiation with visible light in the presence of an iridium photoredox catalyst, a bromide anion, and a nickel catalyst, producing N-substituted α-aryl amides. An analogous carbamoylation reaction of aliphatic CH bonds of alkanes took place when UV light and a diaryl ketone were used instead of visible light and the iridium complex. The present reaction offers a straightforward and atom-economical method for the synthesis of carboxamides starting from hydrocarbons with one-carbon extension.
Copper(II)-Photocatalyzed N-H Alkylation with Alkanes
Donabauer, Karsten,K?nig, Burkhard,Narobe, Rok,Yakubov, Shahboz,Zheng, Yi-Wen
, p. 8582 - 8589 (2020/09/23)
We report a practical method for the alkylation of N-H bonds with alkanes using a photoinduced copper(II) peroxide catalytic system. Upon light irradiation, the peroxide serves as a hydrogen atom transfer reagent to activate stable C(sp3)-H bonds for the reaction with a broad range of nitrogen nucleophiles. The method enables the chemoselective alkylation of amides and is utilized for the late-stage functionalization of N-H bond containing pharmaceuticals with good to excellent yields. The mechanism of the reaction was preliminarily investigated by radical trapping experiments and spectroscopic methods.
Solvent-Free N-Alkylation of Amides with Alcohols Catalyzed by Nickel on Silica–Alumina
Charvieux, Aubin,Le Moigne, Louis,Borrego, Lorenzo G.,Duguet, Nicolas,Métay, Estelle
supporting information, p. 6842 - 6846 (2019/11/11)
The N-alkylation of phenylacetamide with benzyl alcohol has been studied using Ni/SiO2–Al2O3. In the optimized conditions, the desired product was isolated in an excellent 98 % yield. The reaction could advantageously be performed in neat conditions, with a slight excess of amide and a catalytic amount of base. These conditions were tested on a large range of amides and alcohols, affording 24 compounds in 13 to 99 % isolated yields.