23784-47-6Relevant academic research and scientific papers
Organocatalytic Trans Semireduction of Primary and Secondary Propiolamides: Substrate Scope and Mechanistic Studies
Grams, R. Justin,Lawal, Monsurat M.,Szwetkowski, Connor,Foster, Daniel,Rosenblum, Carol Ann,Slebodnick, Carla,Welborn, Valerie Vaissier,Santos, Webster L.
supporting information, p. 172 - 178 (2021/10/14)
We report a chemoselective, phosphine-catalyzed semireduction of primary and secondary propiolamides. In the presence of stoichiometric pinacolborane and catalytic n-tributylphosphine, a variety of propiolamides were successfully converted to the corresponding acrylamides in excellent yield with (E)-stereoselectivity. The reaction condition is tolerant of various functional groups including alkene, alkyne, ketone, or ester. Deuterium labeling studies established that the hydride from activated pinacolborane is added to the α-carbon and the proton on the amide nitrogen is abstracted by the ?-carbon to furnish the (E)-acrylamides. DFT calculations revealed a clear energetic driving force for the (E)- over the (Z)-isomer. (Figure presented.).
Catalytic, transition-metal-free semireduction of propiolamide derivatives: Scope and mechanistic investigation
Grams, R. Justin,Garcia, Christopher J.,Szwetkowski, Connor,Santos, Webster L.
supporting information, p. 7013 - 7018 (2020/09/12)
We report a transition-metal-free trans-selective semireduction of alkynes with pinacolborane and catalytic potassium tert-butoxide. A variety of 3-substituted primary and secondary propiolamides, including an analog of FK866, a potent nicotinamide mononucleotide adenyltransferase (NMNAT) inhibitor, are reduced to the corresponding (E)-3-substituted acrylamide derivatives in up to 99% yield with >99:1 E/Z selectivity. Mechanistic studies suggest that an activated Lewis acid-base complex transfers a hydride to the α-carbon followed by rapid protonation in a trans fashion.
Cellulose supported Pd(II) complex catalyzed carbon-carbon bonds formation
Sarkar, Shaheen M.,Rashid,Karim, Kaykobad Md. Rezaul,Mustapha, Siti Noor Hidayah,Lian, Yuen Mei,Zamri, Normaiza,Khan, Md. Maksudur Rahman,O'Reilly, Emmet J.,Rahman, Md. Lutfor
, p. 2856 - 2861 (2019/01/03)
Corn-cobs are an agro-industrial waste and composed of cellulose mostly. In this study cellulose was isolated from the waste corn-cobs and modified to polymeric hydroxamic acid palladium complex 1 and characterized by using a variety of spectroscopic methods such as field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The complex 1 exhibited high catalytic activity towards Suzuki and Heck coupling reactions of activated and deactivated aryl halides to give the respective coupling products with high yield. Moreover, the complex 1 was recovered and recycled five times with no considerable loss of catalytic overall performance.
Enhancing Ligand-Free Fe-Catalyzed Aminocarbonylation of Alkynes by ZrF4
Huang, Zijun,Dong, Yanan,Li, Yudong,Makha, Mohamed,Li, Yuehui
, p. 5236 - 5240 (2019/09/03)
Zirconium fluoride was utilized to promote efficiently iron-catalyzed aminocarbonylation between alkynes and amines without the use of extra ligands. In particular, this new system is applicable to a wide range of amine and alkyne substrates affording α,β-unsaturated amides in good to excellent yields. Preliminary mechanistic studies reveal the activation model involving interactions of ZF4 with both iron catalyst and amine substrates.
Copper-catalyzed α-selective C–H trifluoromethylation of acrylamides with TMSCF3
Sun, Shang-Zheng,Xu, Hui,Dai, Hui-Xiong
supporting information, p. 969 - 972 (2019/03/08)
A copper-catalyzed α-selective C–H trifluoromethylation of acrylamides with TMSCF3 is described. A wide range of arenes and heteroarenes at the β-position of acrylamides are compatible with the reaction, affording the corresponding (E)-trifluor
Palladium-catalyzed Mizoroki-Heck reactions in water using thermoresponsive polymer micelles
Suzuki, Noriyuki,Takabe, Taiga,Yamauchi, Yoshiko,Koyama, Shun,Koike, Rina,Rikukawa, Masahiro,Liao, Wei-Ting,Peng, Wen-Sheng,Tsai, Fu-Yu
, p. 1351 - 1358 (2019/02/06)
Palladium-catalyzed Mizoroki-Heck reactions were carried out in water using thermoresponsive polymer micelles. The micelles were generated from thermoresponsive block copolymers consisting of a poly(N-isopropylacrylamide) (PNIPAAm) segment and a hydrophilic segment such as nonionic poly(ethylene glycol) (PEG) (2) and anionic poly(sodium p-styrenesulfonate) (PSSNa) (9). These copolymers exhibited lower critical solution temperature (LCST) behavior at ca. 40–50 °C and showed thermal stimuli-induced formation and dissociation of micelles. The copolymers formed micelles in aqueous solution at higher temperature, where catalytic reactions proceeded. At lower temperature, the micelles dissociated to form a clear solution, enabling efficient extraction of the products from aqueous reaction mixture. In the presence of these copolymers, palladium complexes catalyzed the coupling reactions between aryl iodides and alkene compounds inside the hydrophobic micelle cores in water under relatively milder conditions. Extraction of the products from the aqueous solution of 2 or 9 was found to be efficient enough in comparison with conventional surfactants.
Visible Light-Induced Aerobic Epoxidation of α,β-Unsaturated Ketones Mediated by Amidines
Wu, Yufeng,Zhou, Guangli,Meng, Qingwei,Tang, Xiaofei,Liu, Guangzhi,Yin, Hang,Zhao, Jingnan,Yang, Fan,Yu, Zongyi,Luo, Yi
, p. 13051 - 13062 (2018/10/25)
An aerobic photoepoxidation of α,β-unsaturated ketones driven by visible light in the presence of tetramethylguanidine (3b), tetraphenylporphine (H2TPP), and molecular oxygen under mild conditions was revealed. The corresponding α,β-epoxy ketones were obtained in yields of up to 94% in 96 h. The reaction time was shortened to 4.6 h by flow synthesis. The mechanism related to singlet oxygen was supported by experiments and density functional theory (DFT) calculations.
Poly(hydroxamic acid) palladium catalyst for heck reactions and its application in the synthesis of Ozagrel
Sarkar, Shaheen M.,Rahman, Md. Lutfor,Chong, Kwok Feng,Yusoff, Mashitah Mohd
, p. 103 - 110 (2017/04/26)
Bio-waste corn-cob cellulose supported poly(hydroxamic acid) palladium complex was synthesized and it is characterized using some different techniques such as FTIR, FESEM, HRTEM, EDX, XPS, UV–vis, TGA and ICP-AES analyses. The cellulose supported heterogeneous palladium complex showed high stability and catalytic activity toward Mizoroki-Heck reaction of aryl/heteroaryl halides and arenediazonium tetrafluoroborate with a variety of olefins to give the corresponding coupling products in up to 97% yield. The palladium complex was also applied to the synthesis of Ozagrel a thromboxane A2-synthetase inhibitor with excellent yield. The complex was separated from the reaction mixture by simple filtration and repeatedly used up to seven times without significant loss of its catalytic performance.
Synthesis of Amides and Phthalimides via a Palladium Catalyzed Aminocarbonylation of Aryl Halides with Formic Acid and Carbodiimides
Seo, Yong-Sik,Kim, Dong-Su,Jun, Chul-Ho
supporting information, p. 3508 - 3512 (2016/12/26)
A novel method for the preparation of amides and phthalimides has been developed. The process involves a palladium catalyzed aminocarbonylation of an aryl halide, using a carbodiimide and formic acid as the carbonyl source. Experimental data suggest that the mechanistic pathway for this process involves in-situ generation of carbon monoxide from the reaction of formic acid with a carbodiimide in the presence of a palladium catalyst. The method can be used to produce a variety of amides and N-substituted phthalimides efficiently.
Appel reaction of carboxylic acids with tribromoisocyanuric acid/triphenylphosphine: A mild and acid-free preparation of esters and amides
Da Cunha Sindra, Haryadylla,De Mattos, Marcio C.S.
, p. 1129 - 1136 (2016/07/06)
A facile and efficient method for esterification and amidation of carboxylic acids under neutral conditions has been developed. Esters and amides can be prepared by reacting a carboxylic acid (1 mmol) with tribromoisocyanuric acid (0.37 mmol) and triphenylphosphine (1 mmol) in dichloromethane at room temperature, followed by addition of an alcohol or an amine, respectively.
