Article
Chemistry, Multidisciplinary
Sawsan H. Alelaiwi, James R. Mckee
Summary: A direct and effective method for synthesizing primary amine of several polycyclic aromatic compounds through copper (I)-catalyzed Ullmann C-N coupling is reported. This method also allows the synthesis of new N-substituted dibenzothiophene derivatives. The use of inexpensive catalysts and aqueous ammonia as the ammonia source makes this protocol environmentally and economically advantageous.
Article
Chemistry, Physical
Caitlyn P. McNichol, Ethan M. DeCicco, Amanda M. Canfield, Daniel P. Carstairs, Shauna M. Paradine
Summary: We present a ligand-enabled, copper-catalyzed aerobic aminooxygenation reaction for internal alkenes. This transformation proceeds via an amidyl radical pathway, different from the previously established aminocupration pathway, through the synergistic combination of a phenanthroline-based ligand and substrate coordination. The switch in reaction mechanism leads to a broadened scope and accessibility to different substrate classes.
Article
Chemistry, Organic
Mingze Sun, Jingjing Chen, Zhenhua Ding
Summary: A new method for the regioselective cyclization of α-aminated ketones to form oxazolidines and dihydroxazines under transition metal-free conditions has been developed. The reaction proceeds at room temperature without the need for hypervalent iodine reagents and gives good to excellent yields of the products.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Naoki Oku, Tomoya Miura
Summary: A double C(sp3)-H functionalization of ethylarenes with alcohols and N- fluorobenzenesulfonimide is demonstrated. The reaction proceeds in three stages: (1) Cu-catalyzed benzylic alkoxylation of ethylarenes to give 1-(1-alkoxyethyl)benzenes; (2) The resulting 1-(1-alkoxyethyl)benzenes gradually convert into vinylarenes; (3) Cu-catalyzed amino-alkoxylation of the intermediary vinylarenes to yield arylethanolamines. This method introduces C-N and C-O bonds regioselectively at the homobenzylic and benzylic positions of ethylarenes.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Jibin Li, Zheng Liang, Yuzhi Ren, Jian Gao, Ding Du
Summary: A new class of functionalized gem-difluorocyclopropanes bearing acyl groups was synthesized via the N-heterocyclic carbene catalyzed difluorocyclopropanation of alkenes with aldehydes and CF2Br2. This reaction involves a cascade three-component radical relay/intramolecular cyclization process. The protocol features metal- and photocatalyst-free reaction conditions, readily accessible starting materials, good functional group tolerance, and easy scalability. Moreover, this strategy is appealing to pharmaceutical chemistry because it is potentially useful in constructing and modifying bioactive molecules via late-stage functionalization.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Jiateng Wang, Yunqing Zhuang, Jie Zhao, Yusong Bi, Chunyan Li, Gehua Bi, Kai Yang, Xin Huang, Weimin Zhang
Summary: A sequential and efficient protocol for the synthesis of alpha-thiolated enaminones has been developed using copper-TEMPO systems. This reaction exhibits a wide range of substrate compatibility, providing the desired product with good to excellent yields and high stereoselectivity. Preliminary mechanistic studies suggest that the in situ formed enaminone plays a crucial role as the key intermediate.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Organic
Linpeng Liu, Yanyu Jian, Weigao Hu, Shaohu Zhao, Zhang-Jie Shi, Nicklas Selander, Taigang Zhou
Summary: A method for radical cyclization and ring-opening of oxime esters with diselenides has been developed. Both Ni(0) and Fe(ii) catalysts can be used for the selenylation of olefin-containing and cyclic oxime ester derivatives. Using this method, a variety of functionalized pyrrolines and alkyl nitriles can be synthesized in good yields. Additionally, a mechanism involving iminyl radical and carbon-centered radical intermediates has been proposed.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Inorganic & Nuclear
Aleksa Radovic, Nikki J. Wolford, Hongze Li, William W. Brennessel, Hao Xu, Michael L. Neidig
Summary: This study focuses on the ligand effects on reactivity and in situ iron speciation in the iron-catalyzed amino-oxygenation of olefins using a bisoxazoline ligand. Experimental results reveal that the ligand and solvent have significant influence on the speciation in the precatalytic mixture, leading to the formation of different species that affect the reactivity. The in situ experiments provide evidence for the formation of an iron iminyl radical species and suggest that the functionalized hydroxylamine identity can dictate the reactivity observed in these reactions.
Article
Chemistry, Multidisciplinary
Lijun Shi, Mingshan Wen, Fuwei Li
Summary: The study reports a selective method for the synthesis of fused N-heterocycles through palladium-catalyzed tandem reactions, which successfully addresses the selectivity issue in the presence of incompatible step reactions and effectively prevents side reactions.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Applied
Guorong Xiao, Kaifu Wu, Wei Zhou, Qian Cai
Summary: A copper-catalyzed [3+2] cylcoaddition/ alkenyl C-N coupling tandem reaction was demonstrated, providing a method for the formation of triazolopiperidine skeletons.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Yuehua Zeng, Yajun Li, Daqi Lv, Hongli Bao
Summary: A novel copper-catalyzed, three-component reaction has been developed for the direct oxycyanation of various alkenes using aryl diacyl peroxides and trimethylsilyl cyanide. Both unactivated alkenes and styrenes serve as reliable substrates and yield beta-cyanohydrin derivatives. An asymmetric version of this reaction has also been successfully conducted.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Applied
Bita Manavi, Hossein Zahedian Tejeneki, Frank Rominger, Mahsa Armaghan, Walter Frank, Hamid Reza Bijanzadeh, Saeed Balalaie
Summary: This report discusses two distinctive intramolecular cyclizations of o-propargyloxy diketopiperazines achieved via a copper(I)-catalyzed reaction, offering an opportunity for the synthesis of challenging Diazabicyclics and Spiro-Diketopiperazinochromanes with high yields and exclusive diastereoselectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Meng Deng, Mengqi Chu, Nan Li, Guohui Sun, Fei Li, Dade Guo, Guohui Kang, Baoming Ji
Summary: A novel method for the CoIII-H-catalyzed aerobic C-C bond cleavage of tertiary allylic alcohols to access ketones has been developed, which shows excellent chemoselectivity, good functional group compatibility, and high yields. This reaction proceeds through a HAT-initiated peroxide intermediate, and an adjacent glycol-type diradical fragmentation process is proposed.
Article
Chemistry, Organic
Liu Shi, Qiang Xiong, Shu-Yi Wu, Yang Li, Peng Shen, Ji Lu, Guang-Yao Ran
Summary: Novel cyclic vinylogous anhydrides were designed and utilized as five-carbon carbonyl synthons for [5 + 5] annulation with vinylethylene carbonates under chiral palladium catalysis. The strategy exhibited excellent regioselectivity, mild conditions, and broad substrate scope, leading to the synthesis of spiro ten-membered lactones bearing oxindole and pyrrolidinone motif in high yield (up to 99%) with moderate to high enantioselectivity (up to 89% ee).
Article
Chemistry, Multidisciplinary
Wenna Xie, Shiwen Liu
Summary: We have developed an efficient and straightforward method for the construction of derivatives of 4-(arylthio)isochromenones. This was achieved through hydrogen bonding network-assisted sulfenylation and electrophilic cyclization using electrophilic N-thiosuccinimides and 2-silynylbenzoates. The presence of hexafluoroisopropanol as a promoter and the silyl group were crucial for the success of this transformation.
NEW JOURNAL OF CHEMISTRY
(2023)
