Article
Chemistry, Multidisciplinary
Vishal Singh, Khushbu Rajput, Ankush Mishra, Sundaram Singh, Vandana Srivastava
Summary: A microwave-assisted, highly chemoselective protocol has been developed for the transamidation of tert-butyloxycarbonyl (Boc) activated secondary carboxamides with amines. The developed method shows broad substrate scope and good yields.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Victor Adebomi, Mahesh Sriram, Xavier Streety, Monika Raj
Summary: This study successfully addresses the challenge of selectively modifying a specific secondary amide in molecules containing multiple primary and secondary amides, and provides insight into the activation of C-N bonds through density functional theory. It represents significant chemical advances for late-stage modification of peptides and the incorporation of various functional groups into natural and synthetic molecules.
Article
Chemistry, Organic
Ida Angel Priya Samuel Rajan, Saravanakumar Rajendran
Summary: In the absence of a catalyst, base and additive, transamidation of twistless and resonance stabilized N-pivaloyl activated amides was achieved at room temperature with alkyl amines in a short reaction time and high yield. The existence of amidic resonance was confirmed by the bond lengths of C-N and C=O. Amines bearing protic hydroxy and carboxylic acid groups were also found to be tolerated under the reaction conditions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Victor Adebomi, Yuwen Wang, Mahesh Sriram, Monika Raj
Summary: The site-selective reaction at a specific C-N amide bond is a challenging task. By using twisted amides and electronic activation, a particular amide bond can be selectively activated for C-C bond formation even in the presence of similar amides.
Article
Chemistry, Organic
Cong Lv, Ruisheng Zhao, Xiuying Wang, Dan Liu, Tegshi Muschin, Zhaorigetu Sun, Chaolumen Bai, Agula Bao, Yong-Sheng Bao
Summary: Here, we demonstrate the simultaneous activation of alpha-C-H and C-N bonds in unactivated secondary amides by a copper catalyst to synthesize alpha-ketoamides or alpha-ketoesters in one step. This challenging and underdeveloped transformation is achieved using copper as a catalyst and air as an oxidant, and is compatible with a wide range of acetoamides, amines, and alcohols. The mechanism studies suggest that the reaction involves radical alpha-oxygenation followed by transamidation, with the assistance of N,O-chelation and molecular oxygen as an initiator.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Hayeon Moon, Sunwoo Lee
Summary: We report a new method for the synthesis of amides using acyl pyrazoles and nitroarenes under reducing conditions. The method shows good functional group tolerance and has potential application in the synthesis of a variety of organic molecules.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Danfeng Ye, Hao Chen, Zhiyuan Liu, Chuanhu Lei
Summary: The new protocol allows for the transamidation of N-benzyl-N-Boc-amides under transition metal-free and base-free conditions, resulting in a diverse array of substituted amides in good yields. Notably, the reaction preserves enantiopurity with respect to chiral amino-acid-derived nucleophiles. The method has been successfully applied in the synthesis of pro-drugs and the antidepressant moclobemide.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Xinhao Zhu, Kerou Wan, Jin Zhang, Hui Zhao, Yang He, Yangmin Ma, Xiufang Yang, Michal Szostak
Summary: This study reports an extremely mild method for the direct, transition-metal-free esterification of thioamides through the selective generation of tetrahedral intermediates. It represents the first transition-metal-free approach to the thioamide to thionoester transformation in organic synthesis. The ground-state destabilization of single-atom bioisosteric thioamides will expand the arsenal of valuable amide bond functionalization reactions.
Article
Chemistry, Organic
Erdong Qu, Shangzhang Li, Jin Bai, Yan Zheng, Wanfang Li
Summary: In this study, a Ni-catalyzed reductive transamidation was reported, allowing for the synthesis of various amides with good yields and a broad substrate scope. Furthermore, the same catalytic reaction conditions were applicable for N-sulfonyl benzotriazoles, enabling the synthesis of corresponding sulfonamides.
Article
Chemistry, Multidisciplinary
Ida Angel Priya Samuel Rajan, Saravanakumar Rajendran
Summary: This study demonstrates the transamidation reaction of N-pivaloyl activated amides with weakly-nucleophilic amines such as anilines in the absence of catalyst, base, and additives. The reaction proceeds under one-pot conditions, where the amides are activated in situ by the pivaloyl group and reacted with anilines at toluene reflux temperature to yield transamidation products in moderate to excellent yields (60-97%).
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Organic
Ryu Yamasaki, Yuko Okada, Hiromi Iizumi, Ai Ito, Kazuo Fukuda, Iwao Okamoto
Summary: We report a facile transamidation of N-cyano amides with various amines at ambient temperature without any additive. Crystal analysis reveals that N-cyano amides prefer the trans conformation and exhibit reduced double bond character. DFT study suggests that the transamidation reaction proceeds via direct attack of amines on the carbonyl moiety.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Shweta Singh, Jeyakumar Kandasamy
Summary: A developed method for C-C coupling reactions allows a wide range of functionalized N-Cbz amides to react with enolizable esters, ketones, and amides to produce 1,3-dicarbonyl compounds under mild conditions. The reactions proceed at room temperature in the presence of LiHMDS in CPME, resulting in good to excellent yields of desired products in a short reaction time.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Jiamin Huang, Feixiang Sun, Weiping Liu
Summary: In this study, the deoxygenation of secondary and tertiary amides using [Mn(CO)5Br] with Ph2SiH2 or inexpensive PMHS as reducing agents was reported, providing a convenient method for the synthesis of corresponding secondary and tertiary amines. The transformation is operationally simple, proceeds under mild conditions without external ligands, and exhibits high catalytic efficacy and good functional-group tolerance. Furthermore, the generality of this catalytic system was demonstrated by the late-stage modification of bioactive molecules.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Organic
Vishal Kumar, Sanjeev Dhawan, Pankaj Sanjay Girase, Parvesh Singh, Rajshekhar Karpoormath
Summary: This study presents a simple, cost-effective, and catalyst-free method for transamidation of unactivated amides with high yields. The protocol is environmentally friendly and operates under mild conditions, making it suitable for drug synthesis.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Jie Li, Jiaqi Yao, Lingfeng Chen, Dong Zou, Patrick J. Walsh, Guang Liang
Summary: The imide moiety is a well-known structural motif in bioactive compounds and can be utilized as a building block in various processes. A unique feature of the presented method is the use of two different electrophilic acylating reagents, resulting in the formation of unsymmetrical imides with excellent chemoselectivity. Additionally, symmetric imides can be accessed when N-acylglutarimides are used as acylation reagents under similar reaction conditions.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Pengcheng Gao, Jihong Xu, Tongliang Zhou, Yanhong Liu, Elwira Bisz, Blazej Dziuk, Roger Lalancette, Roman Szostak, Dongju Zhang, Michal Szostak
Summary: In the past decade, significant progress has been made in homogeneous gold catalysis. However, the exploration of Au-I/Au-III catalytic cycle has been less extensive due to the reluctance of Au-I to undergo oxidative addition and the stability of the Au-III intermediate. In this study, we report the activation of aryl halides at gold(I) by NHC (N-heterocyclic carbene) ligands, achieved through the development of a new class of L-shaped heterobidentate ImPy (imidazo[1,5-a]pyridin-3-ylidene) N,C ligands. This ligand platform shows great potential for widespread application in homogeneous gold catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Fernanda Liu, Lakshita Anand, Michal Szostak
Summary: Skeletal editing through single-atom insertion reactions involving nitrogen heterocycles has been reported, utilizing electrophilic carbonyl cation equivalents and in situ generated nitrenes. This methodology enables transformation of pyrroles and indoles to pyridines, quinolines, and quinazolines, offering an innovative approach to complex molecular structures by heterocycle diversification and peripheral editing. Considering the significance of heterocycles in medicinal chemistry, biology, and natural products, these methods provide a valuable tool for molecular editing.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Shiyi Yang, Xiang Yu, Michal Szostak
Summary: Transition-metal-catalyzed cross-coupling reactions of thioesters by selective acyl C(O)-S cleavage have been developed as a powerful strategy for the synthesis of complex molecules. In this study, a divergent Liebeskind-Srogl cross-coupling of thioesters was achieved using Pd-NHC catalysis, enabling the direct synthesis of functionalized ketones under mild conditions. The reaction also allowed for the functionalization of complex pharmaceuticals with sensitive functional groups, providing attractive products for medicinal chemistry programs. Furthermore, a decarbonylative Liebeskind-Srogl cross-coupling by C(acyl)-S/C(aryl)-C(O) cleavage was reported, which represents the mildest decarbonylative Suzuki cross-coupling discovered to date.
Article
Chemistry, Organic
Jin Zhang, Xin Wang, Jiale Liu, Xiaogang Wang, Xinkan Yang, Qun Zhao, Yangmin Ma, Ran Fang, Michal Szostak
Summary: Here, we report a mild Ru(0)-catalyzed cleavage of C(aryl)-O bonds enabled by a combination of a Ru-3(CO)(12) catalyst and an imine auxiliary. This method offers rapid entry to synthetically valuable biaryl aldehydes from abundant anisoles. The synthetic utility of this strategy has been demonstrated in sequential processes to construct complex biaryls, exploiting the orthogonal selectivity of C-O bond activation.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Fusheng Bie, Chengwei Liu, Michal Szostak, Xuejing Liu
Summary: A robust palladium-catalyzed decarbonylative alkynylation of aryl anhydrides is reported. The catalytic system of Pd(OAc)(2)/XantPhos and DMAP as a nucleophilic additive has been identified as effective promoters for decarbonylative Sonogashira alkynylation. The present process expands this reactivity to readily available aryl anhydrides as electrophilic reagents for decarbonylative alkynylation.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Boyu Peng, Licheng Dai, Ruzhang Liu
Summary: A mild and efficient palladium-catalyzed methylation of pyrrolidin-2-yl and tetrahydrofuran-2-yl (hetero)arenes has been developed. The regioselective thianthrenation of a wide range of (hetero)arenes generated the arylthianthrenium triflate, and the Pd-catalyzed alkene carboamination and carboalkoxylation reactions produced the corresponding biologically important pyrrolidine and tetrahydrofuran derivatives. Mechanistic studies revealed a syn-heteropalladation pathway for this reaction. The demonstrated late-stage functionalization and enantioselective reaction will promote the potential application of this method in organic synthesis and related fields.
Article
Chemistry, Organic
Yuge Hu, Yanqing Gao, Jiuhui Ye, Zhiqing Ma, Juntao Feng, Xili Liu, Peng Lei, Michal Szostak
Summary: In this study, the first Suzuki-Miyaura cross-coupling of 2-pyridyl ammonium salts using air-and moisture-stable Pd(II)-NHC precatalysts was reported. The highly selective N-C activation reaction was catalyzed by [Pd(IPr)(3-CF3-An)Cl2] or [Pd(IPr)(cin)Cl] Pd(II)-NHC catalysts, resulting in the synthesis of valuable biaryl and heterobiarylpyridines. The utility of this method in the discovery of potent agrochemicals was also demonstrated.
Article
Chemistry, Organic
Shiyi Yang, Xiang Yu, Yaxu Liu, Michele Tomasini, Lucia Caporaso, Albert Poater, Luigi Cavallo, Catherine S. J. Cazin, Steven P. Nolan, Michal Szostak
Summary: The Suzuki-Miyaura cross-coupling reaction enables the construction of biaryl ketones from inert amide bonds. However, the mechanism of C(acyl)-N bond oxidative addition and catalyst effect in this reaction remain poorly understood. This study investigates the use of [Pd(NHC)(sulfide)Cl-2] catalysts for amide N-C bond activation and presents the reaction development, kinetic studies, and reaction scope. DFT studies were also conducted to gain insight into the mechanism of C(acyl)-N bond oxidative addition and catalyst activation. The results suggest that [Pd(NHC)(sulfide)Cl-2] precatalysts could find application in C(acyl)-X bond activation in organic synthesis and catalysis.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Md. Mahbubur Rahman, Qun Zhao, Guangrong Meng, Roger Lalancette, Roman Szostak, Michal Szostak
Summary: In this Special Issue, a new highly hindered Pd(II)-NHC precatalyst, [IPr#-PEPPSI], was synthesized and characterized for cross-coupling reactions. Commercialized in collaboration with MilliporeSigma, this catalyst provides broad access to reaction screening and optimization for academic and industrial researchers. The broad activity of [IPr#-PEPPSI] in various bond activations and its steric and electronic properties were evaluated, indicating its potential for application in chemistry research.
Correction
Chemistry, Organic
Boyu Peng, Licheng Dai, Ruzhang Liu
Article
Chemistry, Organic
Haiyao Ji, Han Cao, Guan Wang, Feifei Xing, Michal Szostak, Chengwei Liu
Summary: We have developed a general method for the direct decarbonylative thioetherification of carboxylic acids using stable nickel precatalysts. This approach allows for the direct use of carboxylic acids as aryl electrophiles and thiols as sulfide donors. The method has excellent functional group tolerance and broad substrate scope, making it a valuable tool for the synthesis of aryl sulfides. The synthetic potential of this method is demonstrated through the late-stage modification of pharmaceuticals utilizing carboxylic acid functional groups.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Md. Mahbubur Rahman, Guangrong Meng, Elwira Bisz, Blazej Dziuk, Roger Lalancette, Roman Szostak, Michal Szostak
Summary: ItBu is the most important and versatile N-alkyl N-heterocyclic carbene in organic synthesis and catalysis. In this study, we report the synthesis, characterization, and catalytic activity of ItOct (ItOctyl), higher homologues of ItBu. ItOct and SItOct, a new ligand class, have been commercialized to facilitate access for researchers in organic and inorganic synthesis. We demonstrate that the replacement of t-Bu side chain with t-Oct results in the highest steric volume of N-alkyl N-heterocyclic carbenes reported to date, while retaining important electronic properties. Coordination chemistry to various metals and beneficial effects on catalysis are also described.
Article
Chemistry, Multidisciplinary
Jiang Nan, Xin Ren, Qiang Yan, Shilei Liu, Jing Wang, Yangmin Ma, Michal Szostak
Summary: A novel hypervalent iodine-induced twofold oxidative coupling of amines with amides and thioamides has been established, which chemoselectively assembles oxazoles and thiazoles. The mechanism involves the generation of ureas and thioureas as intermediates. These findings open up new avenues for exploring oxidative bond chemistry of amides and thioamides.
Article
Chemistry, Inorganic & Nuclear
Pamela Podchorodecka, Blazej Dziuk, Roman Szostak, Michal Szostak, Elwira Bisz
Summary: N-heterocyclic carbenes have attracted significant attention as ancillary ligands for stabilizing reactive metal centers. This study reports a new class of wingtip-flexible NHC ligands that feature sterically-hindered N,C-chelating oxazole donors. The synthesis, characterization, and evaluation of their properties and coordination chemistry to Ag(i), Pd(ii), and Rh(i) are described. The study also presents preliminary studies of their catalytic activity in coupling and hydrosilylation reactions. These NHC ligands are expected to have broad interest in inorganic and organometallic chemistry due to their potential for stabilizing reactive metals.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Pamela Podchorodecka, Blazej Dziuk, Roman Szostak, Michal Szostak, Elwira Bisz
Summary: N-heterocyclic carbenes (NHCs) have been developed as a major direction in ancillary ligand development for stabilizing reactive metal centers. This study presents a new class of sterically-hindered, wingtip-flexible NHC ligands with N,C-chelating oxazole donors, synthesized through modular arylation of oxazole derivatives. The ligands' structure, electronic properties, and coordination chemistry to Ag(i), Pd(ii), and Rh(i) are described, as well as their preliminary catalytic activity in coupling and hydrosilylation reactions. The findings highlight the potential of these NHC ligands in inorganic and organometallic chemistry.
DALTON TRANSACTIONS
(2023)
